Texas is a 'redemption state' so if you want to invest locally, tax deeds are what you should research. Basically when people don't pay their taxes the county can foreclose and then auction their property. This in a nutshell 'wipes out' liens Like mortgages and 'mechanic liens' (if they didn't pay the roofing company etc.), but does NOT wipe out 'superior' liens like those from the state and/or federal Level (Childsupport, IRS, or EPA liens for example). This is why you could still be liable for large amounts if you buy a property w/ a superior lien against it.
There is a lot of research involved in "due diligence" in order to find properties that are worth the investment. And then unless you take legal action to clear the title, the properties can have hurtles when trying to sell. And generally spec king you'll need to hold the property for at least 6 mon, until the end of the redemption period to sell.
I am beginning to invest in tax deeds myself, I believe that if you do careful research, and buy for the right amount, there is substantial profits to be made. I recommend you watch all of the free youtube videos from 'Thetaxsaleacademy.com". I recently bought a monthly subscription to his site and have found it very educational.
Good Luck! Sundai Segadi