Should I expect the seller to accomodate me? 

I got a hold of one turo owner who was very accomodating walked me through it.. brought the car to the airport ( faster pick up than Uber) then when my flight changed the next day to early morning.

If each unit was updated I assume then the rent could be raised to accomodate the upgrades.

I reminded them I have to make reasonable accomodations , but you  pay for it .   

If anything covid amplifies that.The econmoic damage will result in some distressed sales, but as long as you have equity, which most US households have (substantial equity, actually) you can avoid forclosure simply by selling the home.The last thing a bank wants to do is to take back REO, they will accomodate solutions.We currently have 1% distressed sales, a decade ago we have 40 some % distressed sales.

Another thing is that you should be sure that the spaces can accomodate 16x80 mobile homes.

@David Edwards   I am aware of the RSL rules in seattle regarding ADUs - in fact my other investment property - a triplex in seattle - is in an RSL upzoned area and on a large enough lot (8700sf) to accomodate 4 RSL structures so your hypothetical example is pretty much exactly my situation.