2-unit owner-occupied commercial building - DIY snow clearing?

[Kavi S.]

I own and live in a building where the first floor is an active business. 

I already own the equipment to clear the parking lot. But this is my first winter with another tenant in place, and I thought it would be appropriate to hire a service to keep things professional. 

It looks like that cost is going to be $500-$1000 per storm, and our CAM agreement is splitting that 50%. As I only use 10% of the 20-space parking lot, I'm kind of getting annoyed at the premise of paying $250-$500 out of pocket per storm, I'd rather get out there and do the work and pocket $250-$500 per storm. 

So how bad of an idea is that for my liability insurance? Should I open a handyman business and take out insurance?

How should I actually bill this? I'm not required to be following any GAAP protocols or anything when accounting for CAM, I just have a spreadsheet of costs that I'm dividing up and providing to the tenants. I could just use the numbers from the quotes, put that down on the ledger and do the work myself. Of course they're going to see I'm the one doing the clearing, and they're going to balk at the thought of paying for it, and there won't be a receipt. So maybe my own handyman company sending myself a bill legitimizes things? I don't know where their heads will be at. In general I've never billed for my own time in the CAM ledger, but I need to learn a good way to do that regardless of snow clearing, considering I do a lot of the landscaping myself too.