As we evaluate deals, we're wondering if we're being too conservative with our estimates.

Can someone easily explain best way to leverage my new property, etc to be able to get a 2nd, 3rd, etc by only using my properties as collateral?  

A no contingency sale would be more common in a severely distressed non-functional property where there will be so many material defects that the buyer could not feasibly negotiate until they evaluate them.  

I see people without capital no experience or capital being taught to “help” desperate homeowners by tying up their property in a contract they have no way to successfully close without finding someone to pay more; costing the homeowner behind on their mortgage payments to lose valuable time that can easily lead to foreclosure; I see a program taught to students to take over a property ‘subject to”, leaving the seller unable to qualify for further mortgage financing, responsible for a loan secured by a property he no longer owns, and all held together by someone with 0 experience, limited or no capital, and no liability.  

There is no single website to easily find them (that I'm aware of) and if there was, I'd imagine you'd be competing with 1000s of other investors.  

A good company can do a market analysis to see what is the rental rates are for that particular area, do evaluation to see what repairs are needed, take the right pictures for marketing, have multiple ways of posting your property and finally getting the right tenants so you have a piece of mind.

A year or two from now I could easily see the student living borders go to 20th and Dauphine "11th to 19th, Cecil B Moore to Diamond, most investors may be stuck on Broad-18th (19121/19122)"Temple had an on-campus housing shortage so there is defiantly a need.

Not much, but something to keep in mind.They are all good options, I would also recommend a place where you are physically the closest to or can get to easily.

Since then, my cabins have tripled in value - worth easily $800K or more, and have produced $696,XXX in rents.  

It is a matter of evaluating the risk/return on this opportunity vs others out there.