Financing Several Properties

[Donato Callahan]

Hello Bigger Pockets, 

I am a 20 yr. old investor who has been scouring this website and several others learning about real estate investing in hopes of providing a successful future for myself and future family. As such, with my strategy to be buy & holds under 120K, putting some money into it, then renting them out, I kept coming across the question: How do I finance multiple properties? 

It seems like I could purchase and rent out 4 properties with a 20% DP using conventional loans, and maybe even get 5-10 properties through the more demanding criteria, but what then? How do I finance properties 10-??? It can't possibly be all private lenders, owner financing, or hard money, can it? 

There does not seem to be a conventional answer and I am hoping for some clarity. Thank you all very much.