If my current income is unstable, I assume FHA is not going to be any use for me.

Sometimes it means installing piers *underneath* the foundation, which are usually long enough to go through unstable soil and either hit rock or more solid soil. 

I would not recommend doing AirBNB in an unstable building.

Because is not reliable, it is not how a 1-4 asset is valued, it is not smart to base a long term loan on a short term variable unstable income. 

Neighborhood, vacancy (due to neighborhood violence), and delinquency (due to unstable tenant base), along with Chicago Residential Landlord Tenant Ordinance!!!!

In a Polaris Project survey, 64% of trafficking survivors said they were homeless or had unstable housing when they were recruited.

IMO, if a tenant is unstable enough where they can't commit to a 1-year lease at the minimum, then that's someone I don't want to deal with.In addition, I try to start/end my 1-year leases in the summer (July/August), when it is easier to find new tenants.

The tenants also tend to be very unstable in their lives and jobs and turn over frequently.These days I just talk to people on the phone and if they are not realistic I wish them good luck.

I have the funds, and 700 credit score, but unstable income.What are the best options to lock in lending for this deal besides getting a co-signer?

Those people's lives tend to be more unstable with income and the job situation.