Exhibit 10.12E

FIRST AMENDMENT TO AMENDED AND RESTATED UNSECURED REVOLVING CREDIT AGREEMENT

THIS FIRST AMENDMENT TO AMENDED AND RESTATED UNSECURED REVOLVING CREDIT AGREEMENT(this "Amendment") made as of
the 15th day of March, 2005 by and amongAMERIVEST PROPERTIES INC., a Maryland corporation (the "Borrower")KEYBANK
NATIONAL ASSOCIATION, a national banking association (the "Lender") andKEYBANK NATIONAL ASSOCIATION, a national banking
association, as agent (the "Agent").

W I T N E S S E T H:

WHEREAS,the Borrower, the Lender and the Agent entered into that certain First Amended and Restated Unsecured
Revolving Credit Agreement dated October 20, 2004 ("Loan Agreement"); and

WHEREAS,the Borrower, the Lender and the Agent have agreed to modify certain provisions of the Loan Agreement; and

NOW, THEREFORE,for and in consideration of the sum of TEN and NO/100 DOLLARS ($10.00), and other good and valuable consideration, the
receipt and sufficiency of which is hereby acknowledged, the parties hereto do hereby covenant and agree as follows:

1.Definitions.    All the terms used herein which are not otherwise defined herein shall have the meanings set
forth in the Loan Agreement.

2.Modification of the Loan Agreement.    The Borrower, the Agent and the Lenders do hereby modify and amend the
Loan Agreement as follows:



"§3.2Mandatory Repayments of Loan.



3.Waiver.    The Agent and the Lender do hereby waive the Default by Borrower of compliance with the covenant set
forth in §12.1(q) of the Loan Agreement for the fiscal quarter ending December 31, 2004. The Agent and the Lenders have made no agreement, and are in no way obligated, to grant any
future extension, waiver, indulgence or consent.

4.References to Loan Agreement.    All references in the Loan Documents to the Loan Agreement shall be deemed a
reference to the Loan Agreement as modified and amended herein.

5.Consent of the Borrower.    By execution of this Amendment, the Borrower hereby acknowledges represents and
agrees that the Loan Documents remain in full force and effect and constitute the valid


and legally binding obligations of the Borrower enforceable against the Borrower in accordance with their respective terms, and that the execution and delivery of this Amendment and any other
modification documents do not constitute, and shall not be deemed to constitute, a release, waiver or satisfaction of Borrower's obligations under the Loan Documents.

6.Representations.    Borrower represents and warrants to Agent and the Lenders as follows:



7.No Default.    By execution hereof, the Borrower certifies that it is and will be in compliance with all
covenants under the Loan Documents after the execution and delivery of this Amendment, and that no Default or Event of Default has occurred and is continuing under the Loan Documents, as amended by
this Amendment.

8.Waiver of Claims.    The Borrower acknowledges, represents and agrees that it has no defenses, setoffs, claims,
counterclaims or causes of action of any kind or nature whatsoever with respect to the Loan Documents, the administration or funding of the Loans or with respect to any acts or omissions of Agent or
the Lenders, or any past or present officers, agents or employees of the Agent or the Lenders, and the Borrower does hereby expressly waive, release and relinquish any and all such defenses, setoffs,
claims, counterclaims and causes of action, if any.

9.Ratification.    Except as hereinabove set forth, all terms, covenants and provisions of the Loan Documents,
including, without limitation, the Loan Agreement, remain unaltered and in full force and effect, and the parties hereto do hereby expressly ratify and confirm, the Loan Documents and the Loan
Agreement as modified and amended herein. Nothing in this Amendment shall be deemed or construed to constitute, and there has not otherwise occurred, a novation, cancellation, satisfaction, release,
extinguishment or substitution of the indebtedness evidenced by the Notes or the other obligations of the Borrower under the Loan Documents.

10.Effective Date.    This Amendment shall be deemed effective and in full force and effect upon the execution and
delivery of this Amendment by the Borrower, the Agent and the Lenders.

11.Amendment as Loan Document.    This Amendment shall constitute a Loan Document.

12.Counterparts.    This Amendment may be executed in any number of counterparts which shall together constitute
but one and the same agreement.

13.Miscellaneous.    This Amendment shall be construed and enforced in accordance with the law of State of Georgia
(excluding the laws applicable to conflicts of choice of law). This Amendment shall be binding upon and shall inure to the benefit of the parties hereto and their respective permitted successors,
successors-in-title and assigns as provided in the Loan Agreement.

[Remainder of Page Intentionally Left Blank; Signatures on Following Page]



IN WITNESS WHEREOF, the parties hereto have hereto set their hands and affixed their seals as of the day and year first above written.

| |  | BORROWER:                                        
| |  | -------------------------------------------------
| |  | AMERIVEST PROPERTIES INC., a Maryland corporation
| |  | By:                                              
| |  | Name:                                            
| |  | Title:                                           
| |  | [CORPORATE SEAL]                                 



| |  | LENDER:                                                               
| |  | ----------------------------------------------------------------------
| |  | KEYBANK NATIONAL ASSOCIATION, a national banking association          
| |  | By:                                                                   
| |  | Name:                                                                 
| |  | Title:                                                                
| |  | AGENT:                                                                
| |  | KEYBANK NATIONAL ASSOCIATION, a national banking association, as Agent
| |  | By:                                                                   
| |  | Name:                                                                 
| |  | Title:                                                                



Schedule I
to
First Amendment to Amended and Restated
Unsecured Revolving Credit Agreement

Existing Indebtedness

[List]



Debt Summary

|                                                      |                               |                                                      |                                                                       |            |            | March 15, 2005 |           
|----------------------------------------------------- | ----------------------------- | ---------------------------------------------------- | --------------------------------------------------------------------- | ---------- | ---------- | -------------- | ----------
|
|Fixed Rate                                           |                               |                                                      |                                                                       |            |            |                |           
|Teachers Insurance and Annuity Association of America |                               | AmeriVest Plaza at Inverness                         |                                                                       | 1/10/2006  |            | $              | 14,370,197
|Greenwich Capital Financial Products                  |                               | Parkway Centre II Centerra
Southwest Gas Building    |                                                                       | 10/1/2008  |            |                | 37,910,204
|Metropolitan Life Insurance Company                   |                               | Parkway Centre III                                   |                                                                       | 9/10/2009  |            |                | 15,070,941
|Allstate Life Insurance Company                       |                               | Financial Plaza                                      |                                                                       | 10/5/2010  |            |                | 24,045,098
|Southern Farm Bureau Life Insurance Company           |                               | Scottsdale Norte                                     |                                                                       | 4/1/2011   |            |                | 6,553,667 
|J. P. Morgan Chase                                    |                               | Hackberry View1st                                   |                                                                       | 9/1/2012   |            |                | 11,388,359
|J. P. Morgan Chase                                    |                               | Hackberry View2nd(2)                                |                                                                       | 9/1/2012   |            |                | 960,405   
|Teachers Insurance and Annuity Association of America |                               | Sheridan Center Arrowhead Fountains
Kellogg Building |                                                                       | 1/1/2013   |            |                | 28,733,061
|Allstate Life Insurance Company                       |                               | Camelback1st                                        |                                                                       | 9/5/2014   |            |                | 15,855,852
|Allstate Life Insurance Company                       |                               | Camelback2nd                                        |                                                                       | 9/5/2014   |            |                | 4,954,954 
|Security Life of Denver Insurance Company             |                               | Keystone Office Park1st                             |                                                                       | 5/1/2022   |            |                | 4,207,994 
|Security Life of Denver Insurance Company             |                               | Keystone Office Park2nd                             |                                                                       | 5/1/2022   |            |                | 471,308   
|GEMSA                                                 |                               | Hampton Court                                        |                                                                       | 11/1/2007  |            |                | 7,900,000 
|                                                      |                               |                                                      |                                                                       |            |            |                |           
|                                                      |                               | Subtotal                                             |                                                                       |            |            |                |           
|                                                      |                               |                                                      |                                                                       |            |            |                |           
|Variable Rate                                        |                               |                                                      |                                                                       |            |            |                |           
|KeyBank National Association                         |                               | Chateau Plaza                                        |                                                                       | 11/12/2005 |            | $              | 32,900,000
|                                                      | Senior Secured Line of Credit |                                                      | Greenhill Park                                                        |            |            |                |           
|KeyBank National Association                         |                               |                                                      |                                                                       |            |            |                |           
|                                                      | Unsecured Line of Credit      |                                                      | Unsecured                                                             |            | 11/12/2007 |                |           
|                                                      |                               |                                                      |                                                                       |            |            |                |           
|                                                      |                               | Subtotal                                             |                                                                       |            |            |                |           
|                                                      |                               |                                                      |                                                                       |            |            |                |           
|Other notes payable                                  |                               |                                                      |                                                                       |            |            |                |           
|Lease Capital Corporation                             |                               | Phone system                                         |                                                                       | 10/31/2007 |            |                | 59,240    
|                                                      |                               |                                                      |                                                                       |            |            |                |           
|                                                      |                               | Subtotal                                             |                                                                       |            |            |                |           
|                                                      |                               |                                                      |                                                                       |            |            |                |           
|                                                      |                               |                                                      | Total debt, excluding "liabilitiesheld for sale'                     |            |            |                |           
|                                                      |                               |                                                      |                                                                       |            |            |                |           
|Liabilitiesheld for sale                             |                               |                                                      |                                                                       |            |            |                |           
|Jefferson Pilot                                       |                               | Texas Bank Buildings                                 |                                                                       |            |            | $              |          
|                                                      |                               |                                                      |                                                                       |            |            |                |           
|                                                      |                               |                                                      | Total including mortgage loan included in "liabilitiesheld for sale' |            |            |                |           
|                                                      |                               |                                                      |                                                                       |            |            |                |           

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