finding a contractor somewhere I don't know

[Andcake]

Hello
We are in the process of buying a house in an area we don't know. The survey has thrown up a few things that i'd like a building contractor to have a look at - has anyone had this and how did you find reasonable contractors to offer quotes!
Its mostly guttering type things - its for the SE London area?

For some reason, parish magazines are a good source of established local trades, though their prices may not be low. Pick one up in the porch of the church or other places of worship depending on your orientation. Find the local residents association and the committee is bound to be stuffed with nosy busybodies.

Also look out for trade vans outside other houses, ask for a card, write the address they are working at on the back, call back a week or more later and attempt to engage the householder in conversation.

Useful - but my question is more about being a long way away and not in the area so some of these things won't work. I should have phrased my question better

Which Trusted Trader is the hardest scheme to get accredited to and offers customer protection so I would look for someone registered under this scheme. They have already been fully checked out by Which?

trustedtraders.which.co.uk/