Per extensive research on the property the mortgage that is being foreclosed on was taken out in 2004 for 106K.

Can we lower utility costs with energy efficient fixes?

In other words you receive a 30% tax credit on the solar system as well as a 30% tax credit at the least on the roof that is under the solar system (full roof 30% depends on the advice of your CPA).Couple that with the roof now becoming a producing asset and offsetting the utility bill instead of a liability and the increase in appraised home value assuming the solar system is not leased then going solar makes a lot of sense at the same time as replacing/repairing a roof.So in short you don't "get a roof if you go solar", but there are certainly advantages to adding solar to a roof replacement.

Always make sure utility wise you have that all buttoned up as that hurts your noi.

The problem would be getting them to commit and look at this, I know a lot of management firms utilize these deposits for extra revenue but they need to be fair and give you every opportunity to correct. 

Zoning, what utilities are in place or are available, easements, views,  and what a buyer would intend to use the property for are all important factors. 

Make sure you run the numbers for what new construction residences are going for, and subtract out construction costs, cost to install utilities, developer profit, etc, and you can get an idea of what a developer would pay for the lots. 

My intent is to do some rehab, increase cash flow (rents, utilities, etc) and resell in 12-18 months.

In your case you are just waiting until you finish the separate utility items.Hope that helps

That is unless you have extensive construction and property management knowledge to take this one down.