I am in Fort Worth. Many things have been said here that are exactly correct. Like for example 2011 was the best time to buy for sure. By far. Also the selection of homes for sale is small compared to last year. The property taxes are done at the county level but they also vary in different cities within a single county depending on which school district the house is in and a few other details. Generally anything outside of city limits has much lower taxes but not always.
As for foundation cracks I say yes and no. I don't know Dallas county but in Tarrant county (Fort Worth, Benbrook, Arlington, Blue Mound etc..etc..) there are certain spots where that is a problem. For example much of Benbrook is fine but part of Benbrook is really bad. The ground is good and solid in this entire area but there are some neighborhoods built on top of landfills and those are the bad ones. For example the Timber Creek neighborhood in Benbrook (especially down along Timberline drive) is terrible. It sits on top of what was a huge landfill and the ground shifts all the time.
North Benbrook (which is where I live) is not on top of a landfill and I live in the same house my parents bought in 1974. This house has never had a crack and neither has any of my neighbors houses. North Benbrook is the part with a 76116 zip code instead of 76126. Part of the Westpoint neighborhood in Fort Worth is also on top of an old landfill. Westpoint is the part of Fort Worth with a White Settlement zip code (76108). Not all of that area but part of it.
I would be happy to advise anybody as to whether a particular address is on top of an old landfill that I know of. There may be some old landfills I am unaware of but there are many that I am aware of.
It still remains to be seen if all of this natural gas drilling and fracking will have a negative effect on peoples foundations but they are just about finished drilling around here.
Of course that is also another plus as they are very generous with paying whoever owns the mineral rights to the land to explore under it and even more generous if they find some natural gas to drill. But like I already said that is winding down now.
On the property taxes you can file a protest with the county appraisal district each year and usually get them lowered.