The question is for tax purposes, can i write down the down payment this year, or do i write down the whole down payment in 2008, which would have combined payments from 2007 and 2008.Your down payment is not tax deductible.
For a primary residence you can only deduct interest paid on the mortgage/land contract and taxes.
Until you own the home, there are NO tax write offs or consequences.Very little of your closing costs are deductible and NONE of your down payment is deductible any way.