I assume you want to mine altcoins with GPU rigs or are you referring to actual bitcoin mining with asic miners?
Difficulty is increasing at a much higher rate than price, so mining profitability will keep going down despite the bitcoin value increasing.
As an example, with 150 MH/s at the start of June, you could earn around $35 per day. With that same setup, the earnings today would be $10, and that's temporary because of recent price spikes. It was $6-7 the past 2 months.
Even though it may seem that you'll break even after around 8 months, that is only if the profitability doesn't drop further, which would not be the case. Those 8 months can easily become 20 in the near future.
Also, it requires a lot more maintenance than what people initially think. The rigs WILL experience problems, bsods, crashes, driver failure, as well as hardware issues, especially at the beginning while you are still trying to figure out the perfect clocks for the GPUs. I had a problem where the fuses in my apartment would overheat and go off once or twice a day while my rig was working, so I actually had to replace them.
Every rig in terms of heat is like a 500W heater. It might be good at winter, but it is hell in summer and you would have to have constant air conditioning to prevent them from overheating and crashing.
You might think that you can replace a heater with the rigs and save some power, but the sound of 12+ fans at 60%+ without a case
per rig gets old pretty fast, so forget about actually spending time in that room.
In the end, the earnings are not worth it and it would have actually been profitable if you just bought BTC with that money and waited out the same period.
It's riskier, but it is generally more profitable and hassle-free. I would personally suggest to split the money in few parts and invest in multiple newer cryptos. They can easily increase price by anywhere from 10 to 100 times within just a few month. If that happens with just one of them, that's already enough to cover your whole initial investment even if all the other cryptos that you invested fail, plus earn you a good profit.
