@Lucia Rushton hits on the market trends on point.
1. To answer a bit further, the DFW market will not cease to grow as we have too many corporation headquarters, divisions, data centers, and re-leasing happening that will only increase the population and economy.
Houston is also a great market but you need to know which cities to go. Until recently, Houston had a greater GDP than the Dallas Metroplex.
2. Don't go to the high tax areas unless the rents make sense.
3. That's the bread and butter for real estate agents. I'll let you consult an agent of your choice ;)
4. Austin, but again, you must know which areas to go. San Antonio is great and Midland/Odessa is one of the fastest growing cities still.
5. I'm personally working on transitioning to become an investor, so I can't speak for myself. I've seen lots of fix and flips, have yet to meet a wholesaler, but I know they're out there, and of course there's rentals. I have a few friends that are doing Airbnb and they're doing well with that too.
Hope that helps!
Don't hesitate to reach out with any questions, concerns, or need references for any particular city.
Cheers,
Anthony