Would love to meet more people.  

This is a great place to learn and to connect with people so take advantage of all the great resources.

You could give them a thousand bad reviews, if they are the only person in town offering a specific type of product, people will still do business with them.

The first time this happened, the board of directors got an email showing trash everywhere, and HOA management offered to get "their people" out there to clean asap. 

There's a reason that people try to buy properties off-market and that is because you can find sellers who care more about terms than maximizing returns.So start with a conversation: you already presumably have some rapport since it's your landlord and you've spoken before.

Ok so a diff path then my previous post.I also wanted to invest in real estate but just assume( and bet is probably true) that most of the people that find truly good investments have  either or all of the following the most "average joes" don't:1.

I'm doing this exact thing right now- I've been pleasantly surprised by how many people in my network have resources, cash and interest in something like this. 

By poisoning the rats, you're letting them roam free into the world where people's pets can eat them, not wise. 

There are also removable barrier fences and alarms that people use instead of permanent barrier fences. 

It doesn't sound like a showstopper to me.Did you ask the plumber if there is anything people can flush that will help keep the lines clear?