My understanding of the Austin market (please correct me if you know otherwise, I was just an interested observer of the market so as to educate myself before pulling the trigger, not an active participant) is there are two such sweet spots: well below the Austin median (like the $150K area), and way into the stratosphere (like the $1.5M+ area).
Below the median, the fixed costs and time commitments per transaction eat up too much of the flipping profit. In the stratosphere, and their deal velocity slows down too much (plus there are issues with money management, i.e., left holding the bag when the bottom cycle arrives).
Neither of these sweet spots to avoid hordes of cash buyers are likely to appeal to the median HN reader trying to find a residence in Austin. Too low and either the school district is below acceptable performance and/or the commute distance too far (though Austin metro area has it easy commute time-wise compared to places like LA, SF, NYC, ORD, MIA). Too high and unless you are cashing out of an even greater asset-inflated area, you can't afford it.