How hard is it to add a new payment provider? (that isn't one of the built in options)

[cdub]

I have customers all over the world and I'm banging my head against the wall with Stipe and the taxes for each location. I've been thinking of switching over to Lemon Squeezy that uses Stripe but is a Merchant of Record so they handle all of the local sales tax fun.

Payments, Tax & Subscriptions for SaaS ​

Sell digital products and SaaS software the easy peasy way with Lemon Squeezy. As your merchant of record, we handle the tax compliance burden so you can focus on more revenue and less headache.

www.lemonsqueezy.com

How hard is it to add a custom new payment provider? (If I was to hire someone to code it for me)
How hard is it to add a new payment provider? (that isn't one of the built in options)

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