Any guidance or tips would be greatly appreciated!

Pro tip--make sure your exhaust fan in the bathroom is vented to the atmosphere--meaning out to the outside.....go out the roof or out the side of the unit or secured to an opening in a soffit vent grille off the house. 

Yes, I am looking for an online platform to begin self-managing too.

But damned if I can find anything online about landlords using it!

It's a tip I heard from someone which I heard increases the response rate. 

Learn as much as you can for free first before dropping thousands on courses or mentors. 

What are you guys thoughts for my best course of action?

it is already the 6th day of the month, and most of our tenants made the on time rental payment on the 1st.we am copying our attorney soon and will report to the police department for lost $49,987.00 tenant rental income.So far we have called your customer services and online chat but nobody is answering.

You'll get lowballed like crazy and have to deal with a lot of tire kickers of course but if you know what it's worth you can probably find some serious buyers at a reasonable price.

I'd use an approved underlayment.Pro Tip: If it's cheap, it's not good.....at least spend in the moderate range.