I was going to state it simply, "What's in the contract?", but Henning covered it.
Anyone can be sued for anything and unlike some countries where the law states, "Loser pays.", you usually find the legal bill will bankrupt you long before the damages are awarded.
Money spent up-front for a good attorney to set up the LLC, write the standard contracts, and get all the legal ducks in a row are usually money wasted... Right up until the supoena arrives by special delivery.
The usual answer for attorneys to the question of "How much liability do I have?", is... "How much have you got?" A few paperwork roadblocks set up by their peers usually slows them down enough to stop at the negotiating table, and carrying liability insurance that's appropriate for what's being done, isn't to pay for the damages... It's to engage the free fleet of insurance company attorneys backing that insurance.
The more and better insurance, the more guys making six-figures show up on your side.
Cynical, yes. True, though. Ask Cessna how much money a 20 year old improperly maintained seat-track cost them.