If you work with subcontractors, you know its hard to track exactly what they are doing on your sites. You might not know whether they have actually serviced a site or not and you have to go off of what they "tell" you they have completed.
Instead, why don't you use LMN Time for your subcontractors so that you can not only track their hours but also see where they are at all times?
Setup your contractors so that they can login to your LMN Time account to track hours to their specific jobs. Now, we know you don't want them to have the ability to see ALL of your snow jobs, so use the Hide Jobs and Hide Staff functions in LMN Time. This disables your subs from being able to see all of your snow jobs and staff.
Manage your subcontractors with LMN Time so they aren't managing you.