My husband and I have just gone through a living hell with a Party Wall Surveyor's process, grossly over exaggerated estimates, rude Surveyors etc etc.
I was even threaten with costs of £3,000 from the adjoining owners Surveyor until I found the most absolutely wonderful Surveyor who completed the entire process of a rear extension and all the legals associated with their Party Wall stuff for £695.00 + VAT
When considering engaging a Party Wall Surveyor give these guys a call and at least get a quote:
www.localpartywallsurveyors.com