A question about etiquette ...What to expect for a day of helping people?

What the hell is this? You just chiming in to play Devil's advocate?
Are you the type of guy that uses people under the guise of "Friendship" ?
Would you be okay with feeling used after 5 1/2 hours of doing most of the work on someone else's car?
Nope.

But when I offer to help, I either give the help freely...or state my terms for the help I give.

I expect others to do the same when I ask for their help.

I generally give people who help me more than they ask...but that’s a choice. I never expect the same when I offer free help or state my terms.

Feeling “used” means you didn’t get what you expected and up front agreement of terms eliminates that. Like I said, either give the help freely or agree on the terms in advance.

But live with what you get and don’t complain...because you decided which it should be.