Ask HN: How do you deal with accounting for your EU SaaS?

We are running a recurring revenue business in the UK that now has over 3k users (wohoo!) but are having problems with the accounting side. We're way over the Xero soft limit of 1000 transactions per month but struggling to deal with the best/simplest way of accounting for a large number of small transactions. The product is B2B, so all our customers require invoices each month.

How do EU companies deal with this? I think I want to put a single transaction into Xero each time we get paid by Stripe, but the hard part is figuring out the VAT of that amount as some of our products are VAT-able and some are not. I want to avoid having to write anything but I think I am going to have to...

Is there a "textbook" way of dealing with this? Currently we are just going

Stripe > Load of Messy code that breaks all the time > Xero

and thinking this:

ChargeBee > Stripe > ??? > Xero

Would be simpler but it still doesn't appear to get us 100% of the way there...