The banks have provided a number of reasons (they won't lend to missionaries, they don't like that asphalt doesn't come up to the house, etc...different reason for each bank). 

Read books from Bigger Pockets authors, podcasts, independent research, talking to other investors, and pounding the pavement.

The house needs a roof and the existing roof is very old asphalt over cedar shake so according to the roofers they need to completely remove everything down to the rafters and install 5/8th inch plywood then reroof from there (one estimate so far came in at $31k for that).  

I should also mention that the driveway is a mix of extremely old broken up asphalt, dirt, gravel, and slabs.

For example, it might not make sense to ball out and put a new metal roof on a Hilltop duplex when you could just put an asphalt roof on and it will do the same job for cheaper, even if you are holding for a long time.

To be safe with anything except a fairly new house, you’d need to excavate around the house, parge the outside of the foundation with asphalt, install a dimpled plastic membrane over that, and then on the inside, fastidiously install rigid foam on the floor and walls, spray foam/tape all seams, etc… Then frame, then drywall.Seems ungodly expensive.

I love this country mate but it's starting to resemble communism...The most thankless job in all of real estate is property management.It's almost impossible enough to find a legit operator like yourself and then folks request lower fee's.Unbelievable...I don't think folks understand how much time and effort is needed to property manage "properly" and the 10% is peanuts.Sure, if you pay in peanuts you will get a monkey heheTry self managing and many will come back crying in a few months.Just my opinion after pounding the PM pavement for 10+ years now 

In my areas they require concrete or asphalt driveways & parking and each unit requires 2 parking spots, that is 4 spots per duplex, that's 800 square feet of land for parking per duplex.All of this adds up, but it works out, least for us it has.Also...

Only contracted out the cement, Sheetrock, well, and asphalt driveway.

Again, not sure how real this is but it is reassuring that someone is up and running there successfully- The SA covers a complete upgrade of the building - Walkways, roofing, deck pavement, building stucco etc.