- landscaping, snowplowing, tree work (esp given its separate driveway)
Landscaping is a land improvement entered in the assets/depreciation section as a land improvement.
Snowplowing is a standard and common maintenance expense - but only that portion that applies directly to the rental.
Tree work I can't help with, since you don't provide more specifics on exactly what you mean by "tree work". Planting a tree? Removing a tree? Watering a tree? Trimming a tree? Regardless, what's it's impact/relationship to the rental?
- what about property taxes, home owners insurance.
What about it? Is the unit and the property it sits on assessed property taxes separately from other property you own? (Such as your primary residence.) Does the house if it's own separate insurance policy? If so, this isn't an issue as all property taxes and insurance costs are fully deductible.
Otherwise, if what you call a carraige house is what I would call a Mother-in-Law dwelling, you pro-rate property insurance and taxes based on the square footage of space that is exclusive to the renter.
- depreciation : any drawbacks on claiming depreciation? does it affect the main house negatively if and when we were to sell it?
I get the impression you think you have a choice on that. You are required by law to depreciate rental property. In the year you sell the property you are required to recapture that depreciation and pay taxes on it. If you don't take depreciation, then in the year you sell you are required to recapture the depreciation you should have taken, and pay taxes on it. So while depreciation may help for the time it's classified as a rental, it's recapture in the year you sell the property does two things: a) The recaptured depreciation adds to your AGI. b) the increased AGI may have the potential to bump you into the next higher tax bracket.
