how long does it take to get something off credit report if paid
Depends, a repo stays on credit for 7 years, and a bankruptcy stays for 11 years, after you have paid off a debt and they have received payment it should be taken of immediately, but you may want to get a free credit report and check and if it is still there call them and ask them about it.
Simply send them a letter (with proof of delivery) using the contact information found on your credit report. Generally they have 30 days to investigate and get back to you, or the information must be removed.