😁My biggest dilemma is the initial investment for the down payment on the first property.

In my opinion, the biggest mistake first-timers make is not that they buy the wrong thing; it's that they take too long too buy.

The biggest difference between a townhome that has an HOA vs. any other props without an HOA are the bylaws & restrictive covenants.Some HOA's have investor caps & rental rules for short-term, etc. 

But the biggest concern for me is still some of the things you mentioned, maintenance and turnover potential.

The BIGGEST goal in rentals is to attract GOOD tenants, and that almost always means single family homes.

The biggest negative as I write this is that your portfolio is probably down at least 30% along with the rest of us.  

Just like anywhere else I think the biggest challenge is finding homes to flip at the right price and being able to build a team of trades that can complete projects on time, within your budget and with the quality that can sell.With your experience I'm surprised you bought new construction. 

The biggest recommendation I would make is to get an inspection done with a third party you choose.

My biggest suggestion would be to get seller financing and if they won't do it then only buy if its a screaming deal.

There are many neighborhoods in Houston that score in the 70s and up on AirDNA, so it is a good market, but you need to be precise about where you're looking.2 - the submarkets within houston that perform well for STR are nowhere near your price point. continue saving or choose a cheaper market. you're looking at the fourth largest city in the US, and the biggest city in the most moved-to state in the union.