@Jason D.
If you sell your condo and buy a single family home instead of a duplex, what's your plan then? Live in the house for a year or two and then rent it out after you can buy another house to live in? Or just sit tight in the condo for awhile longer? How long do you have to stay there before you no longer have to pay the city back for leaving? Is it really worth it to buy now in this market and forfeit that money to the city?
Rents are solid, but house prices are at near historic highs and the taxes are huge, so finding something that cash flows is a challenge. I'm seeing that most of the investors are flipping.
You're right about there not being many multi-units in Austin; from what I've seen they're all in the central area. I haven't seen any listed in North Austin, Round Rock, Cedar Park, etc. As I'm sure you know, it's pretty much all suburban housing developments up here (I'm renting in Avery Ranch myself). On top of that, most of them are "weird" -- and not in a fun, quirky "keep Austin weird" way, more like an annoying, "how would I deal with this mess?" way.
Personally I'm wary of buying something too far away from the center where there's liable to be a lot of development nearby in the next few years. Speaking of which, you might want to ask yourself how long it'll be before all the developers in town overbuild and the market slumps while demand catches up.