Congrats on all your research so far. You didn't specifically mention it but I will assume your strategy is buy and hold or BRRRR. If you want to break even or cash flow at all, Thesis #2 and #3 are possible, but Thesis #1 is not.
I think for a beginner $300k is way way way too much to deploy and raises the stakes too high. As you know it's a crazy competitive market right now. I would recommending either (A) starting with at least 2 cheaper deals or (B) partnering (short term at first) with someone here who is experienced to do some flips and learn
For A, you could try to buy a couple deals in San Antonio, Temple, or other outlying areas (or outside of Texas). Tie up only $30-50k per deal. In those deals learn to find deals, find/vet wholesalers, evaluate deals, estimate rehab costs, work with and vet both hard money and conventional lenders, property managers, contractors, understand the rental market, etc. And talk to a 20+ investors along the way. After doing that you will be ready to deploy more money successfully.
Also check out this thread in terms of trying to be cash flow positive or neutral:
https://www.biggerpockets.com/forums/759/topics/880886-what-is-your-ideal-buy-and-hold-deal-in-austin-texas?highlight_post=5156260&page=1#p5156260