First-Time Home Buyer Credit - You can use this form to make a payment on the credit you took.
Repayment of the Credit. If you are repaying the credit with your tax return, you are required to file form 5405 only if:
Amount of Credit.
First Time Homebuyer. Generally the credit is the smaller of:
Long-time resident of the same main home. Generally, the credit is the smaller of:
You may be able to make a payment without using form 5405, check the instructions for Schedule 4 in the 1040 instructions.