Contracts for Tree Servicing

[Ryan Johnston]

I'm in the process of hiring some companies to work on the house that I'm about to flip. I got some bids, decided to go with this one tree service company to do some trimming, etc. I sent him over some contracts and I got a call that wasn't the most pleasant. He said he didn't need to sign my contracts because he wasn't working in the house. He's never signed contracts like that and he never will. Or something like that. I was just trying to get him to sign an independent contractor agreement and a scope of work sheet. Give me a copy of his insurance policy (which he is doing) and then he gave me a quote sheet that has the agreed upon work which we both have to sign. 

My question is this: do tree service guys really not have to sign any contracts because they won't be working in the house? What contracts do you get your landscape companies to sign? 

Should also note that this job is only $575 so it's really not much. Just want to make sure my rear end is covered