Missing ductwork and the A/C not working right could have been quickly tested during your walk through.

Asbestos HVAC ductwork and HERS upgrades.

Specifically I think a lot about the smells that travel through the duct work between the units.

Also received the Scope of Work: roof repair, exterior paint, replace rear siding, new exterior doors, new gutter, soffit and fascia repair, clean and seal basement, electrical repairs and new breaker 100 amp breaker, refinish hardwood floors, new vinyl kitchen floor, new furnace and duct work - Estimated $9,100 total."

Duct works goes from package unit to crawlspace to bottom of the floor to the unit.

I’m not trying to rain on anything here but the reality is that measuring Btus delivered to individual units via airflow is by its very nature imprecise - if you want to know why, read on...The size and length of the ductwork is but one factor ( of many) that will yield energy losses while that warm air is being moved to your units.

I was able to get an inspection done and from that I know the main work needed is as follow:Under house crawlspace:some foundation pillars or crumbling and need replacement.Major leaks under main bath causing wood beams deterioration.Multiple minor leaks to wood beams in different areas as well.HVAC duct work is leaking at connections.

What neither of them answered was the costs of adding the units; I have done a few flips in the area and have noticed that the bids depend on a few things:1) how big of units do you need (you probably need 2 of the smallest units honestly)2) is the duct work already ready for the units?

The home is so old there is no central air system... furnace would be new, duct work new...

They ran some of the ductwork in the basement, which has an unfinished ceiling, between the floor joists - maybe you could do that?