President Obama signed an extension and expansion of the first-time homebuyers tax credit on Friday. The $8,000 credit was scheduled to end November 30 will now be in effect till the end of June 2010.

Homebuyers must sign a contract before April 30 and close by June 30. The income limits were also raised: Single buyers can now earn up to $125,000 and still get the full credit while a married couple can earn $225,000.

The bill also made more homeowners eligible to claim the credit on their taxes. For first-time buyers, they still qualify for an $8,000 rebate. But now people who want to trade up can also qualify. Those who have owned and occupied a residence for at least five years out of the past eight can claim a $6,500 tax credit if they close on a purchase by the end of June.

Another modification to the original legislation raises the income limits for program participation from $75,000 for a single purchaser to $125,000 and from $125,000 to $225,000 for a couple.  There are also credits available on a diminishing basis above those income limits.

The bill was passed by the Senate on Wednesday evening and by the House on Thursday.