Tri bike

Your budget will probably dictate what bike you can get. The used bike market is pretty soft where I live, no idea about where you’re at, but your budget will probably limit you somewhat. That said, I was able to score a used 2013 Cervelo P2 for under your budget, a once in a lifetime deal for sure.

The typical brands to look for are:
Cervelo
Trek
Felt
Fuji
Giant
Quintana Roo
Orbea
Cube

Have you considered a nice road bike with clip on aero bars? You’re not going to get that much more benefit from a tri bike over a good road bike at the sprint distance. Just a thought.

IMO the best bang for the buck is the Kestrel Talon here are a few links
https://playtridallas.bikesit.com/a/triathlon-time-trial-bikes/kestr...
https://www.kestrelbicycles.com/bikes/triathlon/talon-x-shimano-105-...
find one used or bikesdirect.com

Thanks for the input! I’ll have a look.

Look for a solid used aluminum road bike and clip on aero bars.

Once you think you want to stay in it long term, time to look at tri bikes.

Did my first tri (a sprint) on my mountain bike. Bought a Kestrel Talon in 2016 and have subsequently done sprints and a HIM with it. I like it quite a bit and the price did not break the bank...about $1,500 not including pedals or accessories like the clip on aero bars I put on it. Price included a fitting from one of the best (if not the best) fitters in the area.