In some areas, there are some really strict rules for creditors when it comes to homestead law.

It does come down to your goals, your time to allocate, your business sense, your ability to bring or raise capital, and what you are trying to accomplish.I am personally not a fan of short term rentals, as it appears regulations in many cities keep making it harder.

Rent-by-the-Room (Long-Term)If local regulations allow it, renting out units by the room might generate more income than traditional long-term leases.

Ensure your attorney is well-versed in lending regulations and set up a strong legal framework.

Regulating rent rates creates less inventory and higher prices.

Very old building as well , my client was very strict with how much money he wanted to invest in the building. 

Temperature control:  It's always naturally cooler downstairs, and in the heights of summer and winter, I just cannot get the temperature regulated for both me and my tenant to where we're both comfortable. 

@Eden Meng contact your Solo 401k administrator regarding regulations regarding leasing  mid term and long term rental properties.They should provide guidance regarding prohibited transactions.

Byzantine planning and landlording regulations.

Consider exploring financing options like FHA loans or conventional loans with low down payments, understanding local regulations, and conducting market research to ensure you can cover your costs.