I wouldn't put your public liability number on there, for the sake of the customers (or contractors) making claims before you've even heard about the issue. You keep that to yourself but mention you're covers for X million for wall and floor tiling and / or plumbing or whatever else. And don't do jobs you're not covered for!
But as said, payment terms would probably be the main thing. If jobs go on for months, you want regular payments at various stages. If material doesn't arrive and you're on the job with nothing to do, I'd come up with a rate for that - so they know they have to be on the ball with materials and whatnot.
I'd also state that late payment may incur a premium, though often the best way to manage this is to do it the other way around, so they have a price X and if it's paid by date Y you'll give them a discount of Z (matching your normal price in the end but getting your payment on time. If it's not on time, they have to pay the premium price).
That sort of stuff.
