Bitrix24 is the best in terms of total flexibility, scope of usefulness and usability from novice to pro and broad spectrum of application from managing cold call prospect databases, employees, AM, inbound, to  managing rehabs, contractors costs, total cost of deal and everything else in-between.  

Normally, it's free to you as the landlord and the applicant will pay.

Tenant applications and screening is done all online and takes hardly none of my time and the eviction process (maybe 1 per year) is a lot simpler than most people make it out to be.

On the application she wrote that she makes 3000$/month and then the finace makes 8000$/month.

I beleive they have an online application that the tenants can complete and pay for.

Other than that, I would just be extra thorough with the rest of their application information. 

Has anyone started out by doing it themselves and switched over to a turnkey solution, or visa versa? 

I'm sure many people do this considering to get the best rates typically you need to withdraw from the HELOC at time of application/approval to get a better rate and not everyone will have an immediate need for the funds even if they take them.

Hello Beautiful People of BP,So I receive applications online and I have a lengthy disclaimer at the end where the applicant types their name as a digital signature to accept that I have the right to verify any info provided, contact landlords, etc.

Does a PM have the resources to do credit and criminal checks, check landlord references and apply standardized screening criteria to all potenital tenant applicants....Yes.