XXXXXX says if I am a foreign national and sell my home in USA, I must pay 10% tax on sell price of my home. - that is not correct - according to the Foreign Investment in Real Property Tax Act of 1980 (FIRPTA) a U.S. real property interest by a foreign person (the transferor) is subject to income tax withholding - income tax responsibility is determined upon filing a tax return - and if there is no income tax responsibility - all withholding would be refunded.
In additional - there are exemptions from XXXXXX mandatory withholding - see here - http://www.irs.gov/businesses/small/international/article/0,,id=102254,00.html
As you are living in the US and have a valid SSN numbers - you are residents for tax purposes - and not a foreign person - and as such you are not a subject of XXXXXX mandatory withholding.
Let me know if you need any help.
Tax Preparer
Taxes, Immigration, Labor Relations