The first thing - The taxes are rather high in Harris County so any taxes owed are bound to be way over $500 before they foreclose and put on the courthouse steps for sale. You would be surprised how many parcels stay on the books late for 10 or more years. The second place a tax foreclosed is not the wisest buy - seldom do you know the chain of title and the previous owner can came back and reclaim in two years.
If this is something you plan to live in yourself and not use as an investment I suggest you look at http://www.bidselect.com
and choose a HUD owned home. Some you can get for $1. down. Contact a HUD certified agent. Now you will get an inspection of sorts and a title policy.