Writing off purchases to improve rental property when partner made the purchases

Question

I bought my split-level house from my mother and moved in. I rented the upstairs to a couple of tenants. They use the upstairs while my girlfriend and I use the downstairs (except for two shared spaces, the kitchen and laundry room). I'm aware that improvements made on a rental property can be tax-deductible.

Given my terrible credit, the house was sold via a contract sale instead of a traditional mortgage. Also due to my poor credit, my girlfriend financed the new appliances and bought a couple of devices for the house (Nest thermostat and smoke detector). I am reimbursing her for them.

Since the house is mine but she made the purchases for the house, can either of us claim the deductions? If yes, do I have to write off only a percentage since I only use the equipment some of the time?

Answer 1

Since you are reimbursing her for the expenses, you can claim them, the same as if you bought them using credit from any other source.

She cannot claim the expenses because she doesn’t own the property.

I don’t know about the second question.