yeah when you setup there is supposed to be a slight relief on the neck off a perfectly straight neck, with the action slightly raised. this is supposed to reduce fret buzz. but the exact amount of deviation depends on the strength of your attack. different people will have different attack.
i wouldn't pay someone to change my strings or polish my guitar either (and such services DO exist, believe it or not). all you need are 2 allen keys and patience. it's as easy as turning a screw. you would be setting up your guitar every time you change strings. bass strings are not cheap either.
proper maintenance of a guitar would be to loosen the strings when in transit. loosening the strings would have an effect on the bow of the neck. to avoid that you would loosen the truss as well. this is to compensate in fluctuations in the weather when you transport your bass. you wouldn't want to pull a bass out of a gig bag to find that the neck has cracked or warped, that would be horrible.
one does not have to be a good player to deserve an expensive, delicate instrument, as long as he knows how to maintain it.
