Whats Your Average Holding Period?

I was just curious how long others are having to hold rehab properties. 95% of the foreclosures in my area are in the "bad" part of town. Bad as in west side, high crime, low income, etc. Typically I buy for 20k, rehab for 8k and sell for 50k. I average 13k per property. My big problem is that I end up holding the property for 9-12 months. I have no problem finding people that want to but it, but finding someone with decent enough credit to get a loan is like finding a needle in a haystack. I always pay closing costs and downpayment (Ameridream, etc) as well Just curious what others do Thanks