Reddit reviews Nestling X2 CREE XM-L U2 LED Rechargeable Waterproof 5000Lm Black Bicycle Bike Light headlamp + 1x Free 5 LED Tail Light with Install Holder + Charger Battery

Second this -- a hybrid is probably the OP's best bet.

He can probably save some money by getting a single speed bike, but he should resist that temptation -- Austin is hilly, and gears are nice.

If he has a friend who knows bikes and can go with him (to tell him what's good and what's not and help him determine if it fits), Frankenbike is often a good place to find a used bike, if he wants to save even more.

If he ever rides at night (and every commuter eventually ends up riding at night), he'll want lights. One can spend a lot on them, but there's no need -- lights like these and these are very good (not 5000 lumens good like the headlight claims, but even the 1000 it really does is very good) and reasonably priced. Lights are way cheaper to order online than buy locally, and while the Chinese knockoffs do tend to be inferior to the name brand stuff, they're generally good enough and 80% cheaper.

Copy/paste from the other post asking about lights. FWIW

I've used this on the helmet for a couple seasons: AKASO USB Rechargeable Bike Light... https://www.amazon.com/dp/B01N6J35PZ?ref=yo_pop_ma_swf

And this on the bar for 2 seasons: Nestling X2 CREE XM-L U2 LED... https://www.amazon.com/dp/B014GWV77C?ref=yo_pop_ma_swf

Both work great. I do about 15-20 night rides per season, each between 1 and 2 hours. I had the magic shine one too. Also good but my battery died and for about the same price as a battery I got this light. Battery interchanges between them too, so that's convenient. The magic light can accept a wide angle lens that spreads the beam, really makes it a winner for a bar mount. Wide Angle Lens for Cree Powered 900 Lumen XM-L T6 LED Bike Light Set for Stupidbright SB1, Gemini, Magicshine. (Clear) https://www.amazon.com/dp/B0178RUEX0/ref=cm_sw_r_cp_apa_T3g2BbC6STZSX