Allowing criminals to simply walk away scot free is a unfortunate side effect of having so many unprofessional landlords.

Many times the seller of the note will provide collateral files that may have some borrower info, and we also research social media, PACER for bankruptcy, and any sources for criminal records to develop as much info that we can to underwrite a NPL. 

@Matt Boyle no offense, but if you are an appraiser asking for tips from agents about price discovery that is sorta a red flag for me.You as an appraiser are considered to be an impartial expert on value, and agents like it or not have an inherent bias and are generally not trained, licensed or required to follow USPAP (Uniform Standards of Professional Appraisal Practice)Refer to link below for differences between USPAP and BPO.https://nationwide-appraisal.com/appraisal-avm-bpo...I am curious as to why you are asking for tips from agents doing BPO's vs seeking advice from professional appraisers in the Chicago land area?

When landlords did not have access to credit reports or criminal background checks like they do now, then charging a half-month's rent seemed fair as they could do what you could not.  

Security deposit plus move-in fees cannot exceed the amount of the first full month’s rentNon-refundable move-in fees are limited to only tenant screening reports, criminal background checks, credit reports, and cleaning fees.Total non-refundable move-in fees are limited to 10% of the first full month’s rentPayment Plans Required –Landlords must allow an installment plan to pay a security deposit, a pet deposit, move-in fees, and last month’s rent.

This is both an offensive and a defensive tactic.

Credit score disqualification, insufficient work history or income, criminal record, etc.

If the previous address is close, march into the court house and look up the criminal and civil filings under the applicant's name.

In talking to the tenant she wouldn't tell me his last name - long story short he was trying to hide his background (multiple criminal, evictions, 5 owi's, etc).  

Example from my last real AD.HOUSE FOR RENT3BR2BAmore infomore infoI WILL ONLY RESPOND IF YOU LEAVE A REAL PHONE NUMBER$50.00 non-refundable application feeTypical Qualifications: 600+ Credit Score| No judgements | No evictions| No criminal background | No smokers| No delinquencies |2 pay stubs| whateverElseIRequire ------------------2) I do this to help reduce the amount of callers that will not qualify.3) If you decide to screen over the phone I ask.