Million Credit membership fee
I place TAS facilities at Type A, B, and some C Starports of a size appropriate to the local population, wealth of the system, and amount of traffic that passes through the system. High population, wealthy systems with Type A Starports will have extensive facilities, with rooms varying from inexpensive basic rooms, to ultra-luxurious suites at higher rates. A facility at a type C starport with a small population, if it exists, might be merely hostel type services, and very limited concierge services, guides, and arrangements with the best of the local businesses to provide services.
The TAS facility at larger Starports might well be the single most luxurious hotel on the planet, with conference rooms, fine dining, an extensive concierge service, and a local supply of the types of gear that Travellers might require. Inventories will vary depending on what sorts of activities are nearby, and items not carried, are contracted through local businesses.
The concierge can arrange guides, security services, rental vehicles, in-system travel, legal assistance, administrative assistance, banking, the aforementioned services like making ship payments from available balances as they might have been instructed.
The TAS will be the premier place to see, and be seen, with non-members vying for invitations by members, as quite a bit of high-level business is conducted on TAS grounds. If the TAS is located within the extrality zone of the star-port, the staff can, and will, generally provide any service legal under Imperial law, regardless of local legality.
The TAS charges for these services, basic services involving an often token payment, but more extensive services will command appropriate fees, but use skilled professionals for what services they offer.