I built into my analysis of each property monthly deposits into that account to cover those contingencies.  

If I think about canceling the contract, I am very sure I'll not get the 10% earnest deposit I already paid.

One last thing: I *think* I've found you on LinkedIn, but I'm not 100% certain without a matching photo.

It has to be secured before we can close, the reason we have requested a 50% deposit and other balance paid once closed.

For example, I often see Buyers purchase property thinking there is a $1,000 deposit but then the tenant claims it was $2,000 because they paid the last month's rent.

(Q3)Security deposit is another area that I need clarifying on.

What happens to original security deposit from original 12mo lease?

Tell them you want your deposit back in full plus compensation for them breaking the lease and any extra costs you incurred (eg did you have a cancellation fee for movers-I doubt it as you said you didn't know when you planned to move in).

So, you definitely want to require a security deposit from them.Lastly, the $1250 in rent wired above is probably misleading.

So it's all about matching the project with the right lender.