The Solo 401(k) also has the advantage of being more favorable for real estate investments using debt-financing such as a mortgage - as the 401(k) is exempted from a small tax called UDFI that an IRA would pay on the percentage of income derived from the borrowed money.If your intention is to have the retirement plan invest in leveraged rental property, I can pretty much guarantee you will find either of the checkbook plans to be much better tools.If you have qualification for the Solo 401(k), the exemption from UDFI on a leveraged property investment will be a nice benefit. 

Only buy it if you can get percentage rent from your drug dealer tenants.Obviously joking, don't buy it.

For instance, is it a percentage of the total loan? 

@Elijah VanDenBerg, as a percentage of rent for repairs and CapEx, I wouldn't discount too much.

We’re using niche.com to research ratings on neighborhoods and what percentage of the general population is renting.

b) if you own 50% at end of land permitting stage, what is a good percentage of ownership to ask for in a long-term syndication?

We will both be hands on in the renovations.My questions are:(1) What is a fair percentage of profits for both of us if we flip houses?

So if I contribute 5% of total acquisition costs, I'd receive 15% total equity and cash flow.After the conversation today I realized I need to get my feet wet and probably should just bite the bullet and just use this as a learning opportunity and just split the percentage based solely on my monetary contribution.

The percentages I provided are what I and, based off what I've seen on BP, a lot of others use when setting aside money for future expenses.

Percentages on vacancy, capex, and maintenance holdouts.