Most retail buyers are represented by Buyers agents and they will end up asking for a commission from your grandparents.

Someone became the "Personal Representative for the Estate of...." and opened up probate. 

I have contributed to both the legal defense fund fighting these edicts, as well as the PAC to elect free market representatives that understand how important housing policy is to both providers and renters.

You can save only half of the commission, because very few people would be comfortable to buy 900k without an agent representing them. 

Please clarify this.Clarification: 1) it's a discussion.2) don't assume all realtors or all people are represented by something you've seen in this, or other discussions. 3) it's a multifaceted world in which we can have the humanity to consider our neighbors as well as our investments, and that is a worthy topic of discussion.  

That is not remotely representative of all PMs.

I would suggest contacting several agents that represent different companies and see what is available in your state.

Is there any efficient way to filter out houses on the market represented by an agent?

I would also recommend finding a real estate agent to represent you, help you with the numbers to see how the house stacks in value/and rents to others in the neighborhood.2) there is always a risk for any tenant not being able to pay, and sure COVID may increase that risk but in my opinion not to the point of it not being worth it to buy investment properties.

I have no idea how long these things take and the firm representing the HOA will not even give me a general idea.