You know, I know it's a crummy answer, but with probably over half of the homes here either rental properties, in foreclosure, or owned by investors and vacant, it may just be something people will have to live with. If you see a house on your street and you have a gardener maybe see what that person would charge you to pull a few extra in that front yard, or go down and do it yourself (general term). If people on the street that lived in their homes all rotated a weekend to pull the weeds, spray the weeds, hire someone to do it whatever, on their street it would take care of the problem. But most investors live out of state, renters don't care it's typically not their job, auctioned homes, well they're owned by the bank and they could definitely care less they'll already lose money on it. It may just be one of those things that you have to suck up when it comes to the vacant homes or rental homes. That or like I said, get together with a few people on your (general term) street, each rotate a weekend in the summer and that should keep them at bay most of the time.
And I wasn't complaining that you call the real estate offices, if you have the time kudos to you, it was just amusing that you don't have the time to flag down a gardener to ask them to visit a certain common area but you can call real estate offices. But like I said, if you have the time kudos to you for doing it and glad that it paid off some of the time.