You would fund the SCBN through the closing by deposited $50,000 into the closing. 

So, for example its been for a while that deposit banks really only care about doing "easy" loans so their good rates are only available to customers with very good to excellent credit and have solid w2 jobs. 

A lot is going to depend on how you're situated and how that matches up with the loan products they offer. 

Has the incomes also risen matching the property prices and the annual tas.

How do we make sure that initial deposit is paper trailed?

One deposit. 

For the applicant that I accept as my first tenant, send them an acceptance letter and collect security deposit + first months rentI am sure there is something (maybe a lot) that I am missing.

This is how the process went for us: the lender wanted a signed rental agreement along with a deposit from a tenant before the loan on the new house could fund.

I also said not to rationalize properties that don't match the criteria I've given.The goal is to make money.  

Security deposit is $1700.