One year is the longest you should sign so you have flexibility to terminate, increase rent, or change other terms after one year.

It is absolutely a strategy that many are using really well and making a lot of money with, but you need the right people, money, and time flexibility. 

Both have been good to work with and have flexible terms.

I know that things are forever changing in the RE market so I wanted to ensure my plans are flexible and easily to adapt to.As a side note, I spend most of my time in the Marine Corps out in Pendleton, I saw San Diego as your location so I'm very jealous!

I'm currently with eXp but they don't allow wholesaling (assignments at least), so I need a new brokerage that has more flexibility.

Stocks allow me to liquidate today and I can have 100k by tonight in my account - it gives me that flexibility - but of course every one has diff goals and perspectives - my goal is to adapt and embrace anything which would create wealth for me.

Yes it is possible but you have to be persistent and call around till you find a lender with some flexibility.

You either need to jump on something immediately, be flexible with your criteria (I didn't exactly have environmental problems on my list of things I was looking for - but I didn't rule the property out because of it - and in the end it didn't have environmental problems) and/or network like crazy to find off market deals and pocket listings.

Taking the 30 year gives you a lower monthly payment and more flexibility with your capital to put into reserves or reinvest. 

However, it will depend on how flexible you are with your needs and wants for a property.