Pasadena has a pretty good rental market but the appreciation rates are terrible. Homes in the Pasadena area are selling for the same price they did 10 years ago. This because Pasadena is just to close to the refineries and the school system is not very good.
Deer Park which is West of Pasadena has the best rental rates versus purchase price in the Houston metro area. The schools are rated well as well. Apperciation is still not great but much better than Pasadena.
Katy and Sugarland have good rental markets but the rents are not as strong versus property values. Plus in your price point it will be very hard to find anything in Sugarland. Another great area for rentals is Cypress-Fairbanks as the school districts are really strong.
If you want to get a better idea of what the rental rates are and what properties are selling for you should check out
http://jameswheelock.erasilverstarrealty.com as that website provides real time sold data found beneath the map portion of the search. All you have to do is check the box that says solds and it will plot them on the map. It gives the 20 most recent closed properties and includes rentals.