Amends the Internal Revenue Code to grant tax rebates of the lesser of net income tax liability or $600 to individual taxpayers ($1,200 for married taxpayers filing joint returns). Allows additional rebates of $300 for each child of an eligible taxpayer.

Provides for a minimum tax rebate of $300 ($600 for married taxpayers filing joint returns) for taxpayers with earned income of at least $3,000. Includes social security retirement benefits and compensation and pension benefits paid to disabled veterans for purposes of determining income eligibility for rebates.

Reduces the amount of such rebates by 5% of the amount that exceeds an adjusted gross income of $75,000 ($150,000 for married taxpayers filing joint returns). Directs the Secretary of the Treasury to pay tax rebates as rapidly as possible. Prohibits: (1) payment of rebates after December 31, 2008; and (2) payment of a rebate to a taxpayer without a valid identification number (i.e., social security number). Provides for payment of comparable tax rebates to residents of the Commonwealths of Puerto Rico and the Northern Mariana Islands. Provides that the payment of a tax rebate shall not be considered income for purposes of determining eligibility for federal and federally-assisted state benefit programs.

Makes appropriations for FY2008 to implement payment of the tax rebates. Directs the Secretary to submit a plan and quarterly reports to the Senate and House Committees on Appropriations on actual and expected expenditures of appropriated funds.

Increases in 2008: (1) the expensing allowance for depreciable business assets to $250,000; and (2) the maximum investment phase-out threshold for such expensing allowance to $800,000.

Increases to 50% (from 30%) the amount of the adjusted basis of certain depreciable property (e.g., equipment and computer software) that may be claimed as a deductible expense in 2008.

Raises the statutory ceiling on the maximum original principal obligation of a mortgage originated between July 1, 2007, and December 31, 2008, that may be purchased by either the Federal National Mortgage Association (Fannie Mae) or the Federal Home Loan Mortgage Corporation (Freddie Mac). Disregards mortgages purchased with the increased ceiling amount for purposes of meeting certain housing goals established under the Housing and Community Development Act of 1992.

Expresses the sense of Congress that Fannie Mae and Freddie Mac should securitize mortgages acquired pursuant to the increased conforming loan limits of this Act if the manner of securitization does not: (1) impose additional costs for mortgages originated, purchased, or securitized under existing limits; or (2) interfere with the goal of adding liquidity to the market.

Establishes a temporary loan limit increase for FHA-insured mortgages in specified high-cost areas for which a borrower received credit approval by December 31, 2008.

Grants the Secretary of Housing and Urban Development (HUD) discretionary authority to increase loan limits in 2008 based upon the size and location of residences in particular areas. Directs the Secretary to publish the median house prices and mortgage principal obligation limits as revised by this Act not later than 30 days after its enactment.