I would recommend a Netspend account - yes it is a prepaid credit card but... it has a really good savings account attached to it.

We had pre-paid the lease 6 months ahead for a $50/month discount.  

I have been living in a property for 3 years. When I had a baby last year my dad paid my rent for me through January lease ends in March of 2017. House was sold at trustee sale. New owner says lease isn't valid which ...

One thing that we did do, and this was actually offered by the tenants before we asked, was have them provide a certain number of months of pre-paid rent.

In the old days, EMDs were always considered as "pre-paid" commissions and placed into the Seller's Broker's account(s), with the understanding that if the deal fell apart, the (Seller's) agent got to keep the EMD.  

True that prepaid rent creates a liability (if you account for it as prepaid rent liability) but its still income.

You aren't going to be able to do much, the scammer is very likely to be out of the country and will request you pay via western union or prepaid debit cards. 

But one area that is not clear to me is "prepaid" costs.

You can protect your interest with a bigger deposit (if legal in your state) or more pre-paid rent.

Not only regarding deposits but it some rare cases (it has happened to me) someone pre-paid 6 months of rent in advance.