I would get with a realtor to pull comps off the MLS. There has been a large discussion on Trulia and Zillow valuations and they can't compare to the mls. Most users on this site do not use zillow or trulia for this reason.
How long do you plan to live here?
How much are you planning to put down? (FHa 3.5% , conventional 5-20%)
A rule of thumb some landlords use on this forum is getting 2% of purchase price in monthly rent. In my own experience I find that the properties that do qualify for the 2% rule need a lot of rehab. I think it is relative to your local market.
Typically good deals in my area are 1.5%+ in rent on purchase price. The higher the rent / purchase price goes, the more rehab you'll need to do.
Where did you get the $1100 rent from? You might also want your realtor to pull rental comps so you know what they are when you purchase it.. and then when you're ready to rent, pull them again to see if rent is going up.
Hope this helps
Danny