Gasoline for Tenant's Snow Removal Service?

Hello,

I live in a duplex and the tenant is doing lawn care and snow removal. For snow removal, they are I purchased the snow blower. Who pays for the gas? They said that they will send the gas receipts to me along with the rent check. Is this OK? I guess I could claim some tax deduction on the gas. How is this normally done?

Any suggestions are greatly appreciated.

Thanks

Lokesh