I actually get that question a lot - "how can I quickly trade between cryptos, dollars/fiat, etc. if I need to?" I use Coinbase, but been exploring different wallets. Most recently, I signed up for Uphold. Not sure if you've heard of that. Blocktrades is another one I came across just using HIVE.
Best,
Adam
RE: Crypto Tip: Have multiple off-ramps ready for your coins