I am currently fixing and flipping but my end goal is buy and holds.

My overall goal is to invest in single family homes, move from one to the other and build up to between 4 to 10 properties.  

My current RE market of Portland, OR is insane right now for my specific goals of entry level SFR or MFR yielding cash flow.

Download the landlord tenant laws for this state and you'll have all your answers,, like you said each state is different so find out from the correct source.Your notice of non-renewal / vacate would be in those regulations,, but ususally a month to month term only required the same for notice period,, given in written form, mailed and copy posted on door.. prior to the 1st of the month.. for a full 30 (1months) day notice period.

Any who, my overall goal is cashflow and to also retire my father.

A goal of mine is to organize a meetup for investors in my area.

Plus those storefronts will be difficult to rent (at least I think so) I would be curious to ask why they are vacant, how long has it been since they have been rented and what type of businesses were in there prior.

What is your end goal?

My word of caution would be to approach carefully and make sure you can hit your financial targets prior to approaching the business this way.  

Your DD period will allow you to verify some of that information, like cross checking the leases that you will now have access to with the rent roll provided to you prior to LOI submission.