If it helps, I do component level Amiga repairs from around New Zealand, and a few international ones.
Freight price make this a bad option, but sending faulty motherboards only (no heavy case) makes it more reasonoble.
Labour and parts prices tend to average around 75 Euros, not including return freight.
I don't do any detailed work to 3rd party equipment, like Phase5 stuff, Apollo boards, etc, due to having no service information and no access to parts. Many of these boards use programmable custom logic devices, the contents is secret to the manufacturer.
But otherwise I'd highly recommend Jean-Jacques from amiga.fr (I think he's Voxel on Amiga.org)