how to know if you found a good foreclosure deal?

[Patrina Lott]

Hi, I found a foreclosure deal in my area which is selling a home for $29,300 by  the bank but home sold for 100,000 + in 2006, area is idea for buyers who rehab and use as rental property and average rent is about $850 in the area and very popular....as a newby trying to wholesale and resell to an investor who will triple their profits what is my best approach?