They noticed that the power line has been literally cut off.

If yours does, turn off the power, and check the main wire connections from the trailer to the furnace, and as many of the connections inside the furnace that you can. 

You assume people will be professional, but power and money corrupts.

Knowledge is power, only when applied accordingly.

Tucker Merihew, Phil Pustejovsky, Max Maxwell, Kris Krohn, Jerry Norton and many others just keep learning, but TAKE ACTION very soon either way 

This is a small project and should prove attractive to several banks if you are a qualified borrower.From a feasibility standpoint the first thing is to check with the city or county to determine what is required for all approvals including site plan and building permits, proffers, water/sewer tap fees, bonding requirements, inspections and CO process and time frame for all approvals.You mentioned utilities are in place but you need to need to check with the utility companies and get an idea of requirements to connect to the water, sewer, power, gas, cable, installation and connection requirements, tap fees, hookup charges, transformer location and relocation, power line and power pole relocation issues etc.Check to see if you have to install any manholes, fire hydrants, curb, gutter, sidewalks, street signs, street lighting any specific street design or access requirements,.Check DOT requirements for access, stop lights and permits, traffic studiesDWQ requirements for permits, permit fees, time framesThis is a broad overview of the process and your civil engineer can handle all of this but it's good for you to know exactly what's required.

I called power company and water and had them schedule to turn off in a couple of days.

I've been involved in the automotive business for about three years and have done everything from washing cars before delivery and stocking parts to closing deals and completing financing paperwork.I've always had a fascination with money - especially the power and freedom that it gave to those who could master it. 

In my short time in diving into the world of REI, I've realized the most powerful skill to have is the ability to network.

DO NOT give them that power or they may try and wield it againAs for the buyer.... they may just be trying to negotiate.....using some leverage that they just received....