How can I effectively rent out rooms for mid-term durations or even secure a 6 month lease?

Like banks, some will never say yes but if you call enough and present your deal and the numbers effectively, you will eventually find one that does. 

You could tell them that they would need to sign a new contract stipulating if they miss rent payments "X" amount of times it effectively terminates the contract.

(sigh)In the case of subto especially there are many risks for the seller that usually outweigh the benefits by a lot: such as messing up their DTI ratio, may not qualify to get another loan, and in worst case scenarios if the buyer rips the rents and doesn't pay the mortgage: wrecking their credit, forcing them to sue the buyer or foreclose on the buyer, and effecting their ability to even rent a home in the next 7 years.

Not saying with the proper structuring it can't be done, but there are usually more effective ways.

Hey Folks,I am looking for Rental property owners around Rochester, MN to ask some general questions about how to find tenants, banks to work with, realtors to work with and how to manage a rental property effectively.

We typically let them know that we'll be raising the rents incrementally and we will sometimes give an increase schedule such as they're now paying $450 and we're raising the rent by $20 effective in two months, and then six months after that it's going up another $20.00 and so forth.

Cold SMS is getting harder to do due to the new A2P compliance rules in effect the last 6 months.

Or would it just even out and have negligible effect (i.e. more supply & equally more demand = nominal gains in appreciate or appreciation stasis).

Cost effectiveness will be of top-of-mind interest to them.