Hello 2l.., sorry can't help on the surveyor question but if you are buying a boat that is in good condition and ready to sail, then all you probably need is a surveyor. But if you intend to buy a project boat that needs a bit of work straight off before the sailing part kicks in, then maybe ask (pay) a shipwright to also have a look so you might have some idea of immediate/future costs to your investment, even if you plan to do all this work yourself. Nearly every job on a boat is bigger than first thought and takes more $$$s. The surveyor I used told me my boat was in very good condition and in less than 6 months I had to remove/replace the rusted out chain locker. Fortunately, I could do a lot of the job myself.
My thoughts anyway. And welcome to the forum, cheers