You can also invest $50 in cloud mining. And each mining hosting has a minimum amount of equipment that you should have, for example, 10 ASICs at least. Both options are very risky.
Why take that particular risk when the profit margin with that amount is going to be very thin (assuming a legit cloud miner) and small?
To me, it's just not worth making a few dollars net profit per month out of $50, as it won't cover any expenses.
Many cloud services offer to buy not a whole asic, but only a part of the hashrate, for example, from 5 or more techhash for bitcoin mining. This will attract many customers who are afraid to immediately invest, or the service will pay a reward in this way to partners who attract new users. I invested a little in such services and was deceived because the services for maintaining and paying for electricity through were more than the profit from mining.