@Brandon BrownCongrats super unique way to get the deal financed.  

I am looking for advice on what are good, normal, or unique agreements when family/friends what to invest in you! 

I am looking to brrrr a property with a partner (my mom). We will be using my cash combined with a loan that she will take out on her 401k. She is doing a 401k loan because she is 58 and does not want to get hit with ...

What might be unique to them?

The dynamic within this development is unique.

It's a bit unique here I think. 

Is it possible to write a promissory note from my LLC once we move the property to me to cover Heloc  repayment?

So when I have borrowed from a 401k previously I typically look to repay it within a year.

The home is unique in that it is connected to a studio apartment, which I had intended to set up and run as an Airbnb listing.

Our adjusted mortgage payment is then based on these numbers:$137,500 "purchase"$41,250 not liquid and left in property (30% of home value)$96,250 pulled out and liquid on a stabilized assetConclusion(Not accounting for any closing costs):We have $71,250 in liquid funds after repaying HelocWe have $46,250 in liquid funds after repaying our bank account for the initial downpaymentWe also have an asset working on the numbers in the analysis below.