I rented out a room in my primary home for 3 months in 2024. I'm trying to claim it on my taxes, but in the rental asset section, how do I determine "cost"...help?

[hilgolson]

I have never claimed a rental before so any support on how to do this would be appreciated. I believe that the personal rental area is 17% of the overall square footage of the home, the common area equals about 63% and my personal bedroom/bathroom area takes up the remaining 20%. I think I might take my purchase price and multiply it by a percentage, but I'm not sure what percentage that would be wit the common areas? Any advice would be greatly appreciated! Thank you in advance!

[VictoriaD75]

Any personal use of the space does not qualify as rental space and is not allowed to be used as an allocation for rental expenses. Expenses for business use of the home are only deductible if the rented space is used exclusively for that purpose; any personal use of the space will disqualify it. You can only consider the rental space to be those areas of the home that are 100% rental use when allocating the square footage. Please see the links below:

Tax Treatment of Home-Sharing Activities

Can I Include Shared Space When Calculating Expenses

@hilgolson