CSS Profile: we rent out part of our home

Any advice how to report this on CSS? Our primary home is characterized as a multi-unit property because above the garage there’s a one bedroom apartment that we rent out. For tax purposes we allocate mortgage interest, property taxes, etc proportionally between the house and the rental. The way CSS asks questions about real estate investment and home equity make it difficult to respond accurately. Has anyone had a similar situation?

From the Profile 2017-2018 FAQs and Glossary:

*Q. We lease part of our house as a rental apartment. Should we consider this a business?

A. No. Report your rental income in PI-120. If you file an IRS Form 1040, this should be found on line 17. Your rental apartment should also be reported as part of your home asset value and not as a separate business.*

https://finaidonline.collegeboard.com/fin/VignetteServlet/VignetteServlet.srv?relativePath=/profile/pdfs/1718_profile_faqs.pdf