Very close to a paved biking path (we call it a "greenbelt" down here in Boise).

Also the extra land may have some additional value, especially if it can be built on (or expanded onto by the existing building).Once you're sure you've got a handle on what your expenses should be the other thing to look very closely at are the deferred maintenance and any building systems that are reaching the end of their life (roof, boiler, paving, etc).

I have considered a long driveway but then I'd be required to engineer, pave and sidewalk the primary access road that borders a creek for several hundred feet.

The amount lent would depend on things such as improvements to the lots (paved roads and such) and the state in which the mfh/trailer are kept.

- can they make me forcefully pave my driveway?

I dont think you can just pave it over.

The home is 1830 sq ft, brick, paved drive, carport, deck, 3 bdrms, 2 baths, roof & windows only 5 yrs old. 

Sometimes I think, from the posts I read on BP, that new investors think that "the streets in Tampa, Florida are paved with gold."

How do i value absence of dedicated paved parking spots for a property?  

You'll have to begin with an education.The road to hell is paved with good intentions, wanting to be right isn't always the right thing.Lastly, hearing "how to" from someone with experience can be dangerous to your future.