For background/criminal/credit checks I recommend TransUnion Smart Move.

If you do not have a permissible use, you will not be given access to the personal information.In addition to complying with these privacy acts, you should understand that, under the Fair Credit Reporting Act (FCRA) (15 U.S.C. sec 1681), the data provided to you by using the LexisNexis® products may not be used as a factor in establishing a consumer’s eligibility for credit, insurance, employment or other purposes by that act.There are criminal fines and civil liabilities for knowingly violating the provisions and restrictions of these acts.

And that there are criminal penalties involved.

No offense intended here, but central PA just does not seem to have expansion that you see elsewhere.

They provide you with an application credit score, eviction history, and criminal background check. 

Considering the fact that they are otherwise great tenants, I would not evict, but I would word the letter in such a way that they are aware that this is their one and only allowable offense.

If you are unfamiliar with the Landlord Tenant law here are a few examples..Landlord can only charge up to one month rent for a security deposit or “advanced deposit” If tenant with a criminal history is denied the law assumes the Landlord denied this tenant because of their criminal history and can be finedIf tenant leaves the unit before their lease is up the landlord has to make good faith effort to fill the vacancy.

And that can lead to very nasty lawsuits and or sellers filing criminal charges if the set up was a rip the rents scheme

That gave me credit history, income verification, criminal records, eviction records, etc and helped me build out a thorough lease. 

Real estate development is not for the faint of heart, so after reading your post, it begs the following questions (and I hope you don't take offense): given you're new to development, why would YOU want to take this on, and why would your friend want you to lead such a project?