Then sell the property and start doing fix and flip or fix and rent. ( I prefer to sell this property as it 100km away from my student rentals. ) Not sure if I should renovate the lower unit to sell.

Personally I prefer single family homes around that median price because that's where the most demand will be not only for owner occupants but renters as well.

If your sister-in-law prefers not to be directly involved, your wife could become the sole owner of the LLC, and your sister-in-law could be given a secured interest in the home after the HELOC is obtained.Additional Considerations:You mentioned owning two other properties.

The last few STR deals I closed where my client used a second home loan, they ended up putting down 20-25%, preferring to have more equity in the property versus giving away thousands in fees to the lender. 

It goes to your preference, of course, but whichever can produce the greatest ROI should be considered.There are many markets in Michigan, for example, where it is cheaper to buy an existing house and fix it up than it is to build new.That may not be the case where you are at or through the construction suppliers and contractors you may have access to.To Your Success!

1) an investor will pay the least for your house.2) An assumable loan will only help if you owe at least 8-%, preferably 90% or more if the sales price for an owner occupant who will pay the most. 3) it’s been a VERY slow winter.  

The property needs to be one we are proud to own and preferably would be willing to rent out ourselves. 

It still seems preferable for this generation of homes in St Louis area.

Financing is also easier since lenders prefer predictable rental income over the fluctuations of STRs or MTRs.Short-Term Rentals (STRs) and Mid-Term Rentals (MTRs) can be lucrative but require more hands-on management.

I also have an investor putting some cash down who would prefer an inspection be done.