When the world is your backyard you don't need interior space. 

Seth Nadreau I understand that interior finishes and the breakdown of the space used can be a big differentiator (a large living room is worth less than a living room + additional bedroom or bathroom) — but are there other reasons someone shouldn’t considered price per square foot?

It is not located adjacent to the easement to get to the interior property.My friend has asked the agent to remove the sign, and suggested that the agent put a small sign adjacent to the easement road, with an arrow, pointing down the easement road and then install his big sign at the property boundary.

Have an excuse that allows you to get to see the interior of all units that allows you to see any problems and what they are doing that csts you money. 

All the interiors are virtually identical.

Because they might have missed a few updates to the interior and maybe fallen behind on maintenance, they might not be expecting top dollar.

Main items of work are ripping out all old carpet, intalling wood laminate in place, installing a shower, and interior painting; possibly a kitchen counter or two.

I already took a look at the home and jotted notes today and it needs a lot of interior work in every room and some exterior work.

So, we got a quote from him to take it from it's present state to texturing and painting of this 1,500 SF house, interior only, and the bid is $5,620 which is $1.25/SF of surface. 

What I do know is basically look at what needs to be replaced (EX: windows, interior paint, flooring, HVAC, roof, etc.) and then 'guestimate' a rough cost for each item.