I usually give my SA a christmas gift as a way of saying thanks for taking care of me. I also make sure I fill out all the surveys with 10's across the board. He make's sure my alcantara steering wheel is always wrapped, and my car is never washed. He's also realistic about my mods (and knows I track the car) and has never questioned a warranty repair.
Once you find the right SA you need to take care of them so they take care of you.
OEM M3 GTS Splitter/Wing/Harness Bar/Rear Seat Delete, Ohlin R&T, Brembo BBK, Akrapovic GT4, Alekshop Oil Cooler, ESS Tune/Pulley, Recaro SPG, 18" BBS FI, CAE Shifter, Vorschlag Camber Plates, Bimmerworld Toe-Links/End-Links/Motor Mounts, RD Sport Front Sway, Turner Solid Subframe/Diff Bushings, Awron Gauge.