This is my market and I live and work in 78610.

There is no one size fits all answer for this question, market to market, and property to property are all different. 

Get it under agreement for less than asking price and offer to bring the loan current and have them carry that loan.The way I see it is they are just getting MLS properties under agreement - the last five I looked at had been sitting on the market for more than 150 days (overpriced) because the payoff of the loan would not be satisfied at lower price point. 

If you just take the 13,835 financed at 6% you are adding 83 dollars a month. so a double whammy.Now, lets consider if rates drop to 5.5% in 24 months (not a prediction just a what if) and you could have refinanced at a much lower costs then the above scenario in what you paid in pre-paid and additional interest. on the other hand, if rates for your same scenario after your 5 year payback period is 9, then you will have an asset with a much lower then current market rent.  

You could put most of your funds in the stock market and access them when needed for a HML.

I took my thrashing as you know in 2020  I do know some of my clients that sell turnkey have been keeping the houses and doing BRRRR instead of selling them to investors that part of the market has slowed signficantly for many in that industry.

Study the market.

Unless you are sourcing properties yourself off-market, REI became much more challenging in 2023, and downright brutal since the start of 2024 here.   

If your aunt isn't in a big rush, another option may be (I'm not familiar with TX law):- Pay your aunt for a Right of First Refusal (means you get a chance to buy it before anyone, but has to be notarized by you and your aunt and filed at the courthouse)- Sell your house on or off market.

Firstly I apologize that I do not have any market insights data specifically, but Houston has been a rough market as valuations have pulled back.