Assuming a partners mortgage as a strategy

[Kyle D Birch]

In the past 5 years, I have flipped 4 houses and purchased/rehabbed a 5 unit building in Chicago. I recently refinanced my multifamily with over $100k in equity. I am under contract for an FHA loan for a primary residence for my family. I am also under contract for a 2 flat in my fiance's name for a conventional loan. We are getting married in July so I wanted to utilize low rates & down payment by having her get a property mortgage in her name.

In my next move to scale, I am curious it would be possible to partner with a lifelong friend to secure a conventional loan. My friend earns $90k a year and rents. I am wodnering if he partnered with me on a BRRRR, could we put the property in his namen get a conventional loan, complete the rehab, rent it out and me assume his loan. I know the loan would need to be assumable which depends on the loan, but from what I have read, so long as it is not FHA or a VA loan, the loan MIGHT be assumable.

I has anyone done this? Is it completely impossible? Any feedback would be appreciated.