sources for income approach for appraisal on 8 unit bldg
Last year I had a fire in my 9 unit mixed use building. There were seven apts and 2 storefronts. The building is mostly gutted and we've taken the opportunity to redo the layout to make it flow better since it is a 90 year old office building converted into the current configuration. We were underinsured and only had the bldg for 8 months when the fire occurred. We will be going back to the bank to ask for a construction loan for the renovations. The renovations are going to be between 600k and 700k. Because of the existing loan the numbers will be very close so it's really up in the air whether we'll get approved or not. I'm juggling the rent numbers with the construction costs against what may be calculated as the appraised value.
The bank has already told me the income approach will be used to approve the loan. I don't know yet whether the same appraiser will be involved in the 2nd appraisal. The loan officer told me he uses a GRM calculation with a value of 7 to do his preliminary analysis to see if it's worthwhile bringing in an appraiser. So in preparation for the appraiser doing a more in-depth analysis, I've been using the bank's GRM calculation to estimate my building's ARV. I tried looking at MLS for apts that have been rented in the area, which is what I assume the appraiser will look at, but in the past couple years there are only 2 apartments that were rented through MLS. I looked at HUD's FMRs which are about in par with my rents however, the FMRs from HUD include utilities and in my bldg tenants pay all utilities so in that context the rents are much different. Note that I do not plan to rent to Section 8 but rather was just using the HUD FMRs as a guideline for my area.
So my question would be for anyone, especially appraisers, reading this, if MLS doesn't provide sufficient listings to show what market rents are for my small-town area, then what other sources will an appraiser be able to use? I want to be able to preview those same sources so I can ensure that my rents will be able to provide a sufficient valuation based on GRM so I know my max budget for construction costs to make the building valuation be above that.
I've also called around to some of the larger apt complexes in the area to see what they charge and based our rent off theirs (with some adjustments). But I don't want to get my hopes up that my numbers look good and then suddenly the appraiser comes back with wildly different numbers that are much lower. When he conducted the original appraisal he low-balled us then on the gross income for the bldg by quite a bit. His avg unit rent came out to be $497 but with the rent we were getting for our units the avg would have been just above $600 at full occupancy. This is despite his report saying he obtained info from market data (but he never talked to me about the bldg while writing his appraisal nor mentioned specifically the source of the market data) so I'm concerned we may get low-balled again and then be stuck with a building we can't renovate.