In the future, either get your Real Estate License so you have access to the MLS, or make friends with a realtor so they can get you comps to get an ARV.  

Is the basement legally considered living space?

They often have access to off-market properties which gives you less competition.

I keep reading about all the weird financing issues in this space so I wouldn't actually put money in until mid 2025 or later.  

Happy to chat, network and compare notes with folks in this space. 

I'm looking for the cleanest & most visible way to access payment history, see amortization schedule, tax documents, etc- much like bank softwares provide. 

Is there a way for me to give them access with the desktop version?

If they do not respond, then they do not get access, and their belongings are legally "abandoned" by them.

I will explore the refi avenue to access the equity.

In this space it's all about building a portfolio, my 1 house clients are at the highest risk because they can only rely on that 1 property, they don't have others to help alleviate the burden.