We've had great success in attracting + retaining good tenants and owners by providing an easy to use online portal.  

We use our property management software system that has a conversation portal that the tenants and owners can converse with our property manager. 

Personally, I have had success locating public MLS websites ( a delayed version of the licensed MLS portals) for specific locales.

5.Are all my invoices uploaded to my owner portal?

This is standard practice for the funding platforms that are doing the right way IMO.  506(b) can be used by the portals, but many that are using this exemption are arguably advertising and should be using heightened screening procedures.  

:speaking of taxes. how much confidence do you have in the online portal where you can check delinquent taxes for cook county ?

Called the tenant to verify whether they were able to register for the tenant portal/electronic payments.

Make sure they are properly licensedAsk about their experience, particularly with the type of property you seek to be managedAsk them what their tenant selection criteria isAsk about their payouts, accounting and datesDo they have tech-savvy features like tenant / owner portals, online payments / applications, etc.Ask about their advertising methodology and who pays for itWhat about maintenance and cleaning - is it in-house, who do they useFinally ask about their management fee structure (too many people decide on this alone).Expanded information is available in this blog post on the same topic.

With the expansion of portal sites like ZTR (Zillow, trulia, realtor.com), the agent no longer controls the data.

They pay on an online portal and voluntarily add $50-$100 monthly.