I don't know where we can exchange our coins in the safest and cheapest way. Because in my opinion Cryptocurrency exchanges are the only best way even if it's expensive, so we can get money from Cryptocurrency coins. What we need to be aware of is, in which exchange we have to exchange our coins. Those are well-known exchanges such as Binance, Indodax, HitBTc and others, I think it's safe. The exchange problem can be hacked, of course it can because this is an Online system, if you want to be safer than hackers then we don't have to try playing Cryptocurrency. Have money, just keep it at home or bank, I think it's safe and won't be hacked.