Local Installer

I've bought from TireRack before, for my M5. Tire/wheels shipped to my home, I put them on myself, etc. Very happy, no problems.
I'm now getting a new MB E-Class (boat SHOULD have docked two days ago) and need winter wheels & tires. However, I'm older now and do NOT want to shlep (schlep?) these around my garage and install them. I realize that there are Local Installers for tires/wheels purchased from TireRack; am I correct in inferring that at least in theory you can have the packages shipped direct to a one of them? If so, what have been people's experiences? Are the installers reluctant to do the work if you haven't bought the tires from them? Do they treat you like second-class citizens?
Can you order from TireRack through them? Yes I know they've AGREED to do this kind of work but I'm not in any mood to fight with them, if you know what I mean.I've looked at some installers in my area (NW Nassau County, NY) and read a couple of reviews but am reluctant to order from TR and have them shipped without at least giving the installer a heads-up. Any specific recommendations (or NOT) for installers in my area?
Thanks in advance for any pointers.
Norman


