Fannie Mae has a Small balance program up to $5 Million, they also have a scattered site program so you can treat residntial like a multi family when locations are not all adjoining. you will need an experienced multifamily lender that understands these programs.
There must be another reason the Commercial lenders you spoke with wont touch it, either the bank is not interested in the type of asset, the deal isnt that good, or they dont like your situation. remember its not always you or the deal, every bank has a plan of what they want on their books, and it can change as well. I know lenders that dont want any residential real estate on the commercial side one time, but other times cant get enough of it. shop some more and you will find them.
I suggest having a good plan to present, be thorough at your meeting, Have 3 years taxes, a PFS, a layout of your past projects and outcomes (success and failures if any, it shows you are humble and how you deal with problems) and your plan for this asset, and BE CONSERVATIVE, never puff the numbers, if you need to puff the numbers to make it look good, its not a deal worth doing!
@Jonathan Marcus Just because a property fits in "residential" doesnt mean you have to finance residential, most of my Single family and duplexes are on "commercial" notes because of my low balances and ease of doing the loan sometimes it just makes sense.