Cannondale Slice. It’s a good entry level tri bike that won’t break the bank. I paid about $1,400.
Finished IMMD, IMNC, IMTX and Redman (full in OKC) on it. It’s not the most comfortable bike in the world but it works.
If you are of means, buy the best you can afford. If you're of more limited means I’d keep looking for used.