I went through this process and just purchased a unit through https://kaboomracks.com/. After listening to tons of podcasts and getting a few recommendations, I believe they are legit. So far working with them has been a good experience.

For calculating profitability, check out the calculator from slushpool - and consider that the price may decrease, and if not, the network difficulty will most likely increase along with the price.
-https://insights.braiins.com/profitability-calculator

I'm paying $0.15 per kwh here in TX which is pretty high... but in the current environment will still be profitable. However, I'm mainly interested in the KYC-free bitcoin and getting some experience with mining before deciding if I'm going to expand my mining operation.

Here are a couple great resources that helped me out in my research:
- https://www.econoalchemist.com/post/home-mining-for-non-kyc-bitcoin
- https://bitcoinwords.github.io/mining-for-the-streets