Either way, you'll likely want to do the final grading first, especially since that will give you the opportunity to grade out the driveway and potentially reuse some of the stone from the construction entrance as the base to the driveway.  

I would imagine adding a second entrance will be expensive.

Basement has 2 entrances (Front and Back) and is half way above curb. 

This house was clearly meant to be a duplex since there are separate entrances and no internal stairs - you can only go from one unit to the other by going outside. 

There is an addition behind the garage that is currently used as a master bedroom, but has its own entrance in the back of the house, a bathroom, kitchenette area, and mudroom that has space for a washer and dryer.

It could easily be a quad as each half has 2500+ square feet on 3 floors (5000+ total) complete with 4 separate entrances.

Up stairs on the third floor is a large finished attic room with two windows(no closet no door to the entrance).

After 6 years some paint (not the whole house) is probably warranted; hallways and entrance ways get chipped up and rough looking.

It was listed about $60k higher than comparable units in the neighborhood because it had a studio apartment with separate entrance in the basement. 

If you can find one that was built before 1972 and has had the basement suite since before then, it could fall under grandfathered rules, which as long as it has windows of proper egress size, interconnected hardwired smoke alarms, and a private entrance, doesn't require much else in the way of upgrades or zoning.