Take note you can only mine Bitcoin with ASIC based machine so CPU and GPU are no longer supported. Even if it is supported it's not profitable due to difficulty.
If I were you better start reading this "
First time/Small miner reference for getting started."
If you still decided to mine bitcoin then for cheap units Canaan.io units are cheap but power-hungry Antminer units is also a great option their latest units is the highest profitability due to efficiency.
Thank you for recommending the Avalon Miners. I'm from Canaan Official. Avalon Miners in Texas are on sale. A1246 are $7-$7.5/T rn. You can check on
for inquiries.