Rd4ector,
I understand your frustration. Try to understand what the guests are actually needing, not just what they are saying.
They are in an area they don't know, don't know the repair shops or availability, and we've all heard how repair shops (and dealers) like to take advantage of out of towners.
"I know a guy who can help with that"
"Here, let me give you a hand"
"There's a local fellow we've had out before that people like"
"Old man Joe down the road can fix about anything"
"Xyz repairs is nearby and is very reasonably priced"
"I can call Jim's mobile repair for you, he's quick and can sometimes be here in an hour, depending on his schedule"
"Is there something we can do to make you more comfortable until someone can come out and get it fixed?"
"You can use one of our rental campers for the night. We'll only charge the difference between camping and the rental (no double charge)"
Or whatever else is appropriate and helpful, you get the idea.
People feel vulnerable, especially when in unfamiliar areas and dealing with breakdowns about which they may know very little.
Sometimes 'Help' really means 'Give me some ideas, help me avoid being ripped off, I would really like an informed opinion, give me some tips, or at least tell me if I can rig it up until I get home from vacation or if I really have to interrupt/cancel my long anticipated vacation for an immediate repair'
Offer what you are comfortable offering. Help when you can. But don't go to the opposite extreme of leaving the guest helpless.
You can still be helpful, even if you can't commit a whole day to a donated repair.
I think you'll find this kind of help will be appreciated, too, and not the confrontational or disappointing response you are concerned about avoiding.
And kudos to you for helping when you can and being concerned enough to bring up the topic in the first place.
