Sure you can just spend $50 and get 100 M/s. GPUs mine monero and there are already a few models with specified or better say estimated hash rate.
You can also search google for "best options GPUs to mine monero" also I think mining with CPU is also a thing.
Just spend $50? I'm assuming there is no mining rig that will bring in 100Mh/s for a mere $50!
Would you be able to suggest some hardware for me to check out? Thanks in advance!