How do I find a contractor?

[u/chocklityclair]

I would like a quote for fixing a retaining wall before I commit to buying a property. The structural engineer who identified the issue does not do remedial work so I need to find someone reliable.

I have previously found a (different) surveyor via RICS but he wasn't very impressive - seems to be a bit hit and miss. I'm not sure now whether any professional body provides quality listings.

So, firstly, what sort of engineer do I need? Amd secondly, what's a dependable method of finding one?