For 1st home buyer only. As far as I know, you could withdraw $10K from your pre-tax retirement account permanently(i.e. 401k) without any penalty according to IRS. If you want to borrow more, then you have to pay back to your own pre-tax retirement account with interests to be paid to yourself "再付利息給自己還 回去". Penalty is about 10% of your withdraw money if you don't return back in a timely fashion.Plus it will add you to your yearly income, leading to high tax amount due to IRS. Rule is company dependent. My former employer speculates $50K or 50%, whatever is less, and you must pay back within x years (i.e. 5/10/15 years). Interest rate seems lower than currently 30 year fixed. In fact I borrowed myself from my own 401k. Please PM me if you want to know my personal experiences, or just post it to my club. http://www.mitbbs.com/club_bbsdoc/CA_RealtyMortgage.html