One thing to remember when itemizing is that your state taxes paid are deductible on your fed return.
In the case of home ownership, simply calculating based on the interest paid is very misleading. Once you enter the land of itemization, things change quickly. For someone who may not itemize because their state taxes are too low, home ownership (even a mobile at < $150k) will vault them into a deduction that exceeds $10,000. Whether the resulting $1500 or so in tax 'savings' is relevant is up to the individual.
What I'm really curious about is how your friend pays half his income in taxes. To get to that figure, is he including sales tax paid throughout the year?
