I’m seeking advice from any investors who have dealt with the pain of owning a co-op in NYC.

Having it in both FL (my domicile) and CT (property location), created double the work and fees in both states.From what I can tell this isn't the right entity structure anyway, so I can imagine it was a pain with many extra costs! 

The driveway is wide enough for 1 car, but long enough to fit 2 cars on it by blocking one in.

So, you should be looking to understand the labor and material costs.Material is usually easier:Anyone you hire will need: drywall patching materials, sanding blocks & paper, primer, paint and the corresponding paint rollers and brushes.Labor may depend on level of skill:How long will it take to prep, patch, sand, prime and paint?

To address parking, one tenant blocking in another in the drive and the late night calls it produces has led me to this policy.   

Get out there around 5pm-6pm and walk around the block, talk to residents if you can and see what they have to say?   

Those may help craft a plan for how to minimize the pain. 

Out of curiosity, anyone care to share their biggest pain points, gripes, or frustrations with building financial models?

You can install water meters (not city ones) that can monitor the water usage but the record keeping and calculations can be a pain.

If the tenant identifies an area of moisture that may be causing growth we immediately address the source of the moisture, replace and damage building material (usually dry wall) and or use mold cleaning solutions/mold blocking primers as required. good luck