I worked the FBO gig (KFFC) for a bit while finishing Comm, then went back to full-time flyin to get this CFI out of the way.
Anyways, as for marshalling, usually if it's an a/c based on the field, they will park themselves (we'd monitor CTAF/UNICOM and they'd let us know where they were taxiing to). If it's a transient a/c, they'll usually park any way they want. If the ramp is slow and it's a quick pickup/drop-off, they might just stop near the door. If it's busy, it may require you gettin out there and "stackin' em up" ha. Side note ---> That's how it was when the NASCAR race came into town. At one time, we had 2 ERJ's from Earnhardt, 3 Challenger 600's, a couple Gulfstreams, a Hawker, and a CRJ.
Pretty much, it's just how/where you wanna park them.