rmdr2
If you search around the internet you will find some aircraft dealers here in the UK. I won't do their advertising for them but there are two that take large spreads in Pilot Magazine and one in North Yorkshire featured on Afors.
As they have public reputations to protect they would be my first call - if only for advice. I'm sure they could assist you as they would be hoping for a sale.
Take a friend who is an owner with you - don't buy without a separate independent engineers inspection......