Make sure you have a back-up plan if that happens - i.e. have cash or ability to quickly refi.

If you have the ability to move every year or 2, you could purchase owner occupied.  

Motivation can be money, but it can be to be closer to family, tired of being a landlord, tired of doing repairs (would rather move to a condo), age and ability to maintain, location transfer, timing...there are a million reasons that make a seller become motivated.But to your point, asking if real estate has enough deals to make money is a bit quizzical.

If you have educated yourself and are confident in your abilities and numbers @Cody Smith then debt is a tool to bring forward your investments so you can get the benefits of the investment now.

I'm curious as to why the previous owner would have rents at 50% below market value, that seems to be extremely low and maybe he knew something about his tenants' financial abilities to pay/not pay.

I have been doing a lot of research on investing (primarily into buy and hold rentals) and the one thing that seems the most unclear is the ability to scale up property acquisitions with obtaining more financing/mortgages.

The mortgage contingency is different: it's about you - and your ability to secure financing. 

Agreeing with @Shawn McCormick, you can represent yourself in transactions and put the buy side commission back into your deals to save you money while having the ability to list properties yourself when you sell.

hello fellow investers i am new to real estate and i am looking for books to read im going on deplyment soon with no internet and looking to expand my knowledge my goal is to house hack a duplex in san antonio TX in the next two years while i go to the university of texas at san antonio to get my nursing degree and become an officer in the air force. looking for any recommendation that has imporved your knowledge ive only read rich dad poor dad and have the bigger pockets beginner guied. 

Waiting for the title to season really hindered my ability to scale my real estate business.