well if you have $500 now and you wanna invest I will advise you to go for ETH. the coin has been pumping up for a while now and dont be surprise the price might reach $1000/ETH by first quarter of 2018. i can not advise you to buy BTC now because the price is very high now. Ltc has not been encouraging for a while now i do not see the coin pumping up any time soon. still around $72 for LTC. token market is not doing fine now but if you want to give it a short you can invest in AION. the token is already listed in two exchange website and it is also on coinmarketcap