[One (M7) General] BarryH_GEG:
Did you read the T&C? It's the same device buy-back service that both HTC and Samsung normally use with the only change being, that during this One offer, the guaranteed minimum is $100. Based on devices being traded-in having to be from a selected list of qualifying devices and that they have to be in good working order (no screen, physical, or water damage) they most likely are worth more than the $100 minimum anyway. For example, you'd get $100 for a used AT&T HSPA SGS2 via the promo and they're going for about $200 on eBay.

Program Requirements. In order to participate in the HTC OneTM Upgrade Program

you must have an eligible used device as defined by the on-line Tool

. You can identify if the used device is eligible by utilizing the drop down menus to pick the make, model, and carrier for the used device. If you cannot find the make or model and believe this is in error, you can contact the program administrator at Clover Wireless. The Program is only valid within the United States.

HOW IT WORKS:

The Tool will reflect the value of a used device based upon the manufacturer, model and condition of the device

("Trade-in Value"). The Tool will generate a receipt which includes an acknowledgment by you that (1) you understand you are selling the device in consideration for the Trade-in Value; (2) by accepting such Trade-in Value, you are giving up full ownership rights to the device; (3) you understand the device will not be eligible for return; (4) you are responsible for removal of all personal information before relinquishment of device; (5) you have been advised of any return policy regarding the purchase of a new device or accessory with the coupon; and (6) you are responsible for deactivating the used device and ensuring you retire any outstanding balance. Limited-time offer expires on or before March 12, 2013 or sooner and may end without prior notice. Trade-in devices must meet minimum criteria in order to qualify, as outlined in the Terms and Conditions.

To receive the $100 trade in value (or actual device trade in value, whichever is greater) in exchange for the Device you trade in, you must register valid email address on the HTC One® Upgrade site, you must purchase and activate a new HTC One by March 31, 2013 and mail in your used Device with a valid Proof of Purchase of your HTC One (copy of UPC or invoice/ receipt showing the IMEI) post marked by April 30, 2013. The prepaid card will be mailed via regular United States Postal Service within 60 days from receipt of both the trade-in Device and required paperwork. Your new HTC One device must be activated and remain in service for 60 days to qualify for the promotion.

Used Devices that are sent in that do not qualify either because a) the model of used Device is not eligible or b) the Device is not in the condition stated or c) does not have a qualifying Proof of Purchase will not be eligible for Program and will be recycled without any payment and any OEM incentives are forfeited.

After your mail-in your used Device, you cannot get it back, even if you return the merchandise you purchased. In addition, you must accept any other Terms and Conditions presented by your wireless service provider that may include specific provisions or eligibility to a particular promotion. Failure to accept the Terms and Conditions, shall impact your eligibility to participate in this Program.​

Here's a link to the site that lists what devices are eligible for trade-in and what they're worth.

http://www.htctradeup.com/htcone/