In my community, almost all of us use such services. Better to pay few bucks than getting headache, mistake, paying more taxes than supposed etc...
also the risks of getting a fine for underreporting, and having to deal with more than just the fine afterward if the finance inspector that will be in charge of your case of 10$ unpaid profits on some shitcoin is himself a piece of...somethign!
I don't know what exchanges OP has used, but if he has activity on the ones that Koinly supports, which are a ton, it's really a no-brainer, just go for it, and don't waste money on some accountant that will charge you sometimes even in the thousands for the same job and who will use for sure also the same piece of software.
^Not sure how much it would cost you to hire one in the UK, but I'll bet it's worth it in most countries.
If OP is not looking at huge sums invested so straight 6 digits in booth assets and profit it really makes little sense to hire an accountant nowadays with all the programs around that need only clicking, it's good to hire one if you have a ton of other income sources and you plan on optimizing those, in this case, it's a different story but just for crypto, no, at EU/UK level prices a really good one will charge you over 50 euros per hour, and I swear, these hours are just some 15 minutes long in this profession.