This is not necessarily a bad thing, plenty of legitimate companies use this service.

If you feel the tenants are hinting that you pay for it, I suggest you instead hire a specialist to "service" the door and make sure all sensors work -- which in this case, you say they work properly. 

@David Frey Thank you for your service!

Usually you can have the initial consultation applied if you use their services.

The safe harbor applies to amounts paid during the tax year to acquire or produce what the regs call a “unit of property” (UOP), you must meet these requirements: (1) at the beginning of the tax year, the taxpayer has written accounting procedures treating as an expense for non-tax purposes amounts paid for property costing less than a specified dollar amount (which will be 2500 for you), or with an economic useful life of 12 months or less;.(2) the taxpayer treats the amount paid for the property as an expense on its books and records in accordance with its accounting procedures. ( do this on your bookkeeping software or whatever you utilize)(3) the amount paid for the UOP doesn't exceed $2,500. as substantiated by invoice.Note: The cost for the Unit of Property includes additional costs (for example, delivery fees, installation services, or similar costs) if these additional costs are included on the same invoice with the tangible property.Eg:A purchases 100 printers at $500 each for a total cost of $500,000 as indicated by the invoice.

Both doors are exposed to Wisconsin weather.The service door to the detached two car garage has a lock on the entry knob but no deadbolt. 

One I bought from a neighbor , one from a drive by while doing service calls , one from a customer , and one from a friends mother after she went to assisted living . 

She started a second truck to double our service business (still legally 100% my business), is getting a graphic design degree to freelance as a side hustle, and is 100% on board with my RE goals (albeit she doesn't nerd out on BP Like I do).

Renovations are under way next week and once we get some data back once it’s in service, I’ll let you guys know. 

A single car garage should get as much rent as a single storage unit.If you use the garage, I would not run separate electrical service.