In the US we have home inspectors, and we have surveyors. A home inspector is generally responsible for auditing the structure and mechanicals of the home for issues. A surveyor is only responsible for identifying property boundaries.
A home inspection is under $1000, usually $250-500. I don't know what a survey costs as I've never been involved in a property boundary dispute as US homes are generally on large enough plots that encroachment issues aren't that common.
They aren't, OP makes it sound like it costs an arm and a leg. The costs are around £300-400, about £500 if you want to pull out all the environmental reports as well, which while not insignificant in itself, is not really a big deal when buying a house for hundreds of thousands of pounds.
Fair enough, I don't know anyone who bought a house this way though. For me personally it was always 1) find a house 2) ask the bank to do the survey 3) based on the survey either carry on with the mortgage or retract my offer. Yes I probably couldn't do 5 houses at once, but I have done 3 houses consecutively this way before, no issues whatsoever with the banks.