With my limited experience explained, here's the situation.I have ear marked a good amount to start real estate investing.

Even then I keep my ears to the ground because a good guy can go bad due to human problems.

They are definitely the fastest way to get your phone ringing with motivated sellers.If you don’t want people to see you putting out the signs or don’t have time, just run an ad on Craigslist for someone to do it for you.

Ring doorbell or similar camera to check on who comes in and out, and smart thermostat so you can change the temp before guests arrive or when they leave.

I can tickle your ears all day with fake platitudes or "Hang in there, kitty!" 

Find yourself a good local housekeeper, treat them well with the occasional bonus and they will be your eyes and ears. 

I have a SFR close to Wake Med that is nearing lease end and am all ears.

They collect rent and you have to chase them for it, and I think they have a ring of deadbeat tenants that go from one house to the other, and pay a security deposit and nothing more

Quote from @Zhen Yuan: Use the tool between your ears.

I opened a new host account to handle guest interactions myself, hired a local handyman for emergencies, and found a cleaning person who could also act as my eyes and ears for any required handyman services.