I have coinbase but the fees on day trading were very high. I now use binanceUS. I also have bittrex which is cheaper than coinbase but binanceUS is the best of the three. Currently, it’s free to trade bitcoin. BinanceUS did give me crap for awhile until I jumped through all the necessary hoops to prove I was actually me, due to the new KYC(know your customer) laws. I blew them up on Twitter until they helped me. Tweeting negative things gets their attention fast!
The best way to go is buy your bitcoins, buy an external wallet that only you can access like nano ledger x, send the bitcoins to your wallet, and then send your bitcoins wherever you want. This way you can never be accused of sending bitcoin to nefarious sources.