However, they will pay a double deposit and some other fees.

Yup they hammer folks for the non refundabel deposits.. high pressure is how they are taught to sell.

This needs to be highlighted in the lease and acknowledged by them.Security Deposits: You can’t use their security deposit for routine cleaning, but if they leave things in bad shape beyond normal wear and tear, it’s fair game to deduct cleaning costs.I’d start by having a straightforward talk with them about the importance of keeping things clean for health reasons and property preservation.

For Guarantee I think in the way David your thinking about Guarantee the only one out there is FDIC insured deposits with the full faith and credit of the US Gov. 

I used furnished finder and keycheck to find tenants, screen them, and collect rent/security deposits. 

Deposit that money into a cd or mm with them.  

The information is typically - lease start and end date, how much rent is, what the security deposit is, and how much in advanced rent there is.

With really bad credit I do require (in addition to first month and security deposit) 1/2 to a full last month's rent and/or a good honestrenter.com score.

It’s been 3 months since I made the deposit .

Damage is always on the tenants and comes out of their deposit.