We added a door that we deadbolt to separate our side from the airbnb side, and I had to have some electric outlets and an overhead light to the airbnb side, but other than that everything was updated already and we just had to furnish the property which was really nice and made the process pretty easy. 

@David De La Torre it is common for electric and gas to be turned off when a tenant moves in, forcing them to turn it on in their name. 

New roof, new water heater, new Electrical panel, New HVAC, new Concrete driveway, new Concrete steps & walkout basement, Open space of kitchen and living room, fully finished basement with wet bar and new full bathroom, new windows.

The fourth thing they have is engineered hardwood flooring.

Smaller ones are filling up within 12 hours and the large unit they left with 2x 5 gallon water jugs to empty into AND a catchment below....because obviously the sellers knew that it fills over 5+ gallons in just TWO DAYS.We have had to get a structural engineer in who has noted other water damage throughout the basement (unfinished) that was hidden behind sellers boxes and personal items during our inspection. 

There's an axiom in Engineering that says one problem doesn't cause a failure, but combine a series of problems, and failure almost becomes inevitable.

I love the idea of renovating your carriage house - does it have any water and electric hookups already?

Engage architect/civil engineering - If you are buying land to start development and not just land-banking, I'd engage with an architect immediately.

The past couple of years as L3Harris has begun to move production/engineering from California to the area (cost cutting measure, not political), we have been seeing 10% appreciation yoy or so. 

This means thousands of dollars more in engineering, surveyor, and architectural cost plus months of extra work.Original 2-story garageHISTORIC CONSIDERATIONSTo complicate things further, the structure is located within a historic district.