IMO clear in REALTOR provided contract - that heating/cooling structural electricity are included as inspection items.  

You are correct Steve and to clarify my point is that the cost of waste (which is the fear of most landlords in the scenario) is $100s vs the cost to separate , run new lines, add heating units, add hot water heaters,and add AC units which could push $10,000. 

martins heating and air. only guy I use!

That being said, you obviously do need to have a great deal of knowledge in those areas.I myself have an electrical contractors license, am certified in residential and commercial wiring and have a degree in Heating and Air conditioning and twenty years experience doing all of the above.If you do work in one particular town the municipalities building department and inspectors will also get to now you and see what quality of work you do

.- Verify the existing installation for heating and water heater (new heating system on 3rd floor)- Remove asbestos insulation and pipes in the basement- Verify the existing electrical installation and upgrade to support new appliances- Some windows to be changed and we may consider to change them all depending on pricing- Repair the roof if neededWe are also considering doing most of the work on the unit we would live in (other than plumbing and electricity) but we really need to find a GC that can work within our budget!

What about roof and heating system?

Brand New French Windows, Copper plumbing, Central A/C and Heating, Recessed Lighting, and Flooring throughout.

Tenant agrees to not make alterations, changes or additions to plumbing fixtures, light fixtures, heating units, or locks.Tenant agrees to hold Landlord harmless for any mechanic’s liens or proceedings that result from Tenant actions.Any alterations or additions made by Tenant become the property of Landlord when Tenant vacates.

You might encounter new room additions, a newer second floor, as well as old steam heating systems still kicking around.  

Update - it took me 2 years to get it done but I ended up buying vacant lot on the intracoastal and about .25 mile from the beach and built elevated house at cost of $90 total sf and $170 heated sf.