You're more likely to have a conventioal offer accepted in a compettive market too. 

And if one or all of the elder relatives are incapacitated we should not assume that Lonell is going to take advantage of them by accepting their interest in the property without offering a fair return. 

I have my downpayment save for a first house hack but haven’t had any offers accepted and other homes don’t cash flow.

I would check if there are any options like that available in Norway.Also, banks may be willing to accept a lower down payment on a house if it is a multiunit and other units are already leased when you buy it.

You can't win if you don't play the game.Thanks, Crazy enough I kept submitting offers and got an offer accepted for my second property.

Whatever form you accept, give the renter a receipt with a copy of the payment and both your signatures so it's documented.As for a sublet agreement, Google is your friend.

Any tips or past experiences on either options would be gladly accepted to help make my decision on which route to go with.

You took photos of it when they moved-in as the accepted standard.2. 

Your problem (should you end up in court) MAY end up with the tenant stating you did accept partial rent late and did nothing about this so why the eviction now?

@Gi'angelo Bautista Two things that come to mind is appraisal and market acceptance.