We looked at about 8 houses, put in an offer, got the survey back, pulled out, did the s same again and then settled on our final house - so we viewed about 15 houses in total.
I would recommend getting at least a homebuyers survey if the house isn't new build. We did and it was worth the money, as we were able to negotiate money off the house. A friend at work didn't and has had nightmares with her house (damp, subsidence). I'm not wanting to scare you, but if you are going to spend that much money, its worth getting it checked out. If you aren't sure, you can always call up the surveyor for an off the record chat. We did and his opinion made us change our mind about one house.