If lets say I have $500 to start with, what should I buy and why?
Really man? You are confused with the TRON and ETH? Thats really surprising to know fact that someone can get stumbled upon in the situation like this. The answer for this is off course ETHER from my side. Look at the TRON, it is penny stock exchange with pink sheet profits! It cant do much for you besides ,making you await for long log time and give nothing in return. So be careful if you think that its cheapest coin and you can get huge quantities of it. Sometimes quality is important as well dude.