It might be feasible still buy on Coinbase in small amounts like $10 per week worth of cryptocurrency, then once a year you realize the long term gain, allow Coinbase to calculate your capital gain tax, and when you sell you don’t sell but move it to (ahem) “someone else’s “ off line wallet from which they “never spend.” The advantage is you are in a safe environment when you buy (2FA), no one mugging you at a coffee shop, and unlike a BTM the fees for buying are very low. I move my cryptocurrency first to GDAX and then from GDAX I “withdraw” to offline Segwit wallet. Then I allow Coinbase to calculate the tax.