I am renting out a cottage on the property where I live. Every expense is auto-divided. How would I deduct a full expense which applies only to the rented cottage?

[nils-andermo]

For example, a plumbing repair in the guesthouse, my landlord insurance, supplies, and cleaning are now reduced to 20% of the amount entered.

[PatriciaV · Accepted solution]

If you have asked TurboTax to do the math for you on your rental property that is shared with your residence, you will need to do a little math of your own to report the separate expenses in full.

If you rent 20% of the property and one of separate expenses should be a total of $100, multiply that number by 5 and enter the result for that expense: $500 x 20% = $100, which is the result you want. The difference isn't reported anywhere on your return, so the gross-up is used only to report the correct amount for the rental.