For the past few years we've been using and have had good success with TruGreen/ChemLawn.  I think we pay $38 x 8 sprays per year.  Not surprisingly the spray does seem pretty toxic.  That said I don' t know for if that's the case but I'm guessing there may be more specific info about what's in their spray on their  site. 

I've heard that there's some new service out there that uses less toxic stuff (or not toxins at all) with similar results.  If I find the name of this service I'll post it and let you know.

Also, I add the following tags to your post - lawncare, recommendation, trugreen, chemlawn

Btw, bummer about those heels...