According to the IRS, you must reside in the property a minimum of three years to retain the credit. It looks as if you will have to pay a portion back.
Here is a helpful link with information about the tax credit and the requirements:
Hope you find this useful.
Prudential Connecticut Realty
You would most likely want to wait for 3 yrs to pass so you don't have to give back part of the $8000.
Sounds like to me that you should consider a short sale before you default and just walk away waiting for the lender to foreclose. Sometime lenders don't foreclose for a long time and you continue to be obligated for HOA fees, late fees and the HOA lawyer costs until they do foreclose. HOA debt does not go away.
If you qualify for HAFA , you may even be entitled to get "moving expenses" ranging from $2500-$35000 depending on your lenders. If you move out that option can go away. Usually the number is $3000, but in come cases Chase (if they are the actual investor and not just a processor) have paid $35,000, but you need to ask keep an eye open for their offer letter.
You may also be a better candidate for bankruptcy. Without all the facts and professional advice, you wont know.
To answer your question about $8000 Tax credit you have to stay in home 3 years if not you have to repay in full. The IRS has really good resources for this info, here is a link http://www.irs.gov/individuals/article/0,,id=233589,00.html
but my suggestion would be to work on a short sale or something of that sort, it has less effect on credit, less negative effect on the neighborhood, it is better for everyone, and if you complete prior to Dec. 31 of 2012 the tax implications on primary residence are less. Again IRS has page for that Mortgage Debt Forgiveness Act...
Here is a resource for short sale help.
best of luck to you.
If that is true, you are guilty of FRAUD and maybe a few other things.
I will not contribute to your scheme and I will not wish you good luck.
You are the reason that the banks are screaming and probably will look for a Deficiency Judgement.
I hope I'm wrong.