If it's a black glue that could be asphalt or even asbestos.

There wasn't any oil, but the pavement is old

The report revealed it needed a roof as well as the structure below the asphalt shingles, there was mold in lots of different places, issues with plumbing and electrical, and more.

One problem is, rather than replacing the rotted metal roof with another metal roof, the previous owner just boarded off the built-in gutters and put asphalt shingle roof on.

I'm also looking for someone to come give an estimate on paving what is currently a gravel driveway with asphalt.  

Late to the thread, but did you build a relationship with a local KC concrete/asphalt  guy Andrew? 

You can only allocate a couple % for this - the other regularly recurring expenses like roto rooting, regular tree trimming, asphalt sealing, etc can all be allocated as part of your diligence and be pretty firm year over year.

After more research I most certainly agree with you on choosing the asphalt over the metal.

Standard home being: 8’ ceilings, avg $4/sf tile and flooring materials, RTA China imported cabinets, asphalt shingles, vinyl windows, basic hardscape and landscape, no pool.

Have you seen that the Keys are experiencing Salt Water Intrusion that is comming up through the asphalt in the roads down to Key West?