There are a few self-contained guides that you can access here: https://www.biggerpockets.com/guidesIf you haven’t been to it already, the Bigger Pockets blog features links to their fantastic podcast and many great articles: https://www.biggerpockets.com/renewsblog/

I like the search features: https://www.biggerpockets.com/search

Make sure you understand CAP rates, ROI, Cash-on-cash, etc.Get real good at extracting investor expectations from them.

How old and in what condition are the big-ticket features (roof, windows, doors, flooring, furnace, water heater, etc.)? 

Not to mention all the headache dealing with the tenants, repairs, etc.If I sell the property, I will make (after cap gain tax @15%) around $550k.

FHA loan limits in Austin for 2 units are around $550,000 so you're pretty much capped there using 3.5% down and that's around $35k so you're good.5.

Is it a high cap rate or a lower cap rate market?

An investment broker in NYC would be of no use in California.Also, the analysis is important if you set what you're looking for. i.e. cap rate, positive cash-flow, etc. 

There was an episode of the podcast that featured a woman who had created a property management platform that allowed the owner to turn on/off features like maintenance services and subscribe for a flat monthly rate rather than a % of rent. 

As I've mentioned in a few of my previous post, you really buy here for the capital appreciation, not the cap rate, best of luck in your search.