We are looking for a cloud based (hard wired) security system for a mid-sized apartment building.

Karen, I won't be attending but I can recommend a tip that could save you thousands of dollars: Leave your credit cards at home.Most of the free / low cost seminars give you a few crumbs of information but are mainly sales presentations designed to "upsell" you on more expensive "boot camps" and/or "mentoring programs".They all follow the same classic sales formula, they'll tell you that it normally costs $X (you can even go on their website and see that price) but "today only" or "only for the first N people to sign up" they're putting on a special deal.They'll do the whole "this is how much it would cost individually but here's an incredible package deal" etc.

Our initial financing fell through and we had to scramble to secure backup financing.

One can easily borrow a million bucks against their securities for around 3 pts.

I did not offer any compensating factors like a cosigner or double the security deposit. 

Technology allows us to exchange documents securely online.Browse this forum, and you will see about 20 tax accountants sharing knowledge here.

Is this a secure strategy for decreasing vacancies?

It also helps should you want to secure financing from that bank in the future.  3. 

It has worked out extremely well with unbelievable returns in the 30-40% return rates not including the equity appreciation of now having secure long term tenants paying huge lease rates.

Is it legal to put a tenant's (or multiple tenants') security deposit into a savings account and then collect the interest that the deposit makes for you?