I have been working with an agency to put solar panels on my roof and have signed all the loan paperwork for 2017 but due to scheduling I won't get a slot till 2018. Does that make me ineligible for the tax credit? What if I do end up getting a slot and it's installed in 2017 BUT I don't have permission to operate from the city yet?
The solar panels have to be installed on the home and paid for before you can claim the tax credit.
See IRS Form 5695 Residential Energy Credits instructions on page 1 - https://www.irs.gov/pub/irs-pdf/i5695.pdf