I am new in this forum. What mining equipment would you suggest. I have about 3500$ to invest.
Mining is only viable right now IF you expect the price of BTC to go up. For comparison, I sold a 10ghz miner back in Feb or march for 500 bucks or something like that, right now it is worth about 20 dollars or less. DO NOT BUY mining equipment. IT IS NEVER WORTH IT honestly. even buying mining shares makes you lose money, unless you only hold on to them for a short period then sell then wait for price to go down(which it does) then rebuy.
The future bitcoin price shouldn't be considered in the decision at all.
If you can get more bitcoin by spending your money to buy bitcoin directly than by buying some miners, you should go buy some bitcoin regardless of how much you expect bitcoin to be worth.