But I am a bit scared of stagnant winter sales in the northeast.

Just to add our local specifics: make sure how your landlords/owners want to handle turning utilities after tenants move out: in the winter it's critical.

I am no expert on Florida or Winter Springs, so I cannot give you specific advice on what to adjust for in your area without spending time learning that area.

My thoughts are to get them on a 6 month lease in Nov. at $1100/mo, and then start an annual lease In June, whIch Is a more favorable tIme to fInd tenants vs. the wInter In MN.

Coming up to the winter months I'm nervous it'll only become harder to find someone!

And keep in mind the weather here in the Willamette valley can be daunting for the very long wet dark cold winters.. 

the one disadvantage of month to month is if the tenant decides to move out in the winter slow months.

Usually once a house is abandoned and in foreclosure, a preservation company applies the orange stickers saying this house has been winterized or has lock changes, etc.

These are typically more like corporate housing or traveling medical professionals.Short term rentals—We've used Airbnb selectively as a way to turbo-charge properties that maybe have a small funky unit that can't command strong rents but still is a bear to heat in the winter. 

Large house = $1,500/mo ($900 for 3 bed, $600 for 2 bed)Small house = $1,100/mo ($550 for each unit)I see a huge opportunity here to buy these houses this fall/winter and let the current leases expire and then rehab them next spring/summer just in time to rent to nurses/young professionals working at the hospital.