There was a thread about this exact topic a few months ago but I can't find it. Here are some of the ideas I remember....
1) The Mark spell has to be cast on a specific object to "attune" it to that location. The object needs to be in the wizards hand when the Teleport spell is cast. This way, a wizard can Mark pretty freely since the more Marked object he has, the bigger a logistic hassle it will become. This is the Ultima way. The marked object can be bought or sold.
2) Depending on the type of object, the Mark may not last long. Wooden object might only last a few hours, silver and gold a few months, while gemstone might last years.
3) An ordinary mundane object might become attuned on its own if it sits in the same spot for a long time. Thus, the party thief can sneak into the king's kitchen and steel some silverwear to allow the rest of the party to teleport in.
4) Their might be alternative way to attune stuff. For example, wood elves might be able to teleport from one tree to any of that tree's seedlings.
Aaron