I sincerely hope nothing like that will be implemented on classic ever. AH is what killed L2 economy, and I'm not talking just about a global one. Essentially what a local ah will do is create easy to access lists of available items with the ability to sort by price. A potential buyer would only need to teleport between cities to identify the best price, and it would take seconds (not to mention because of convenience only 1 particular local ah would be used by everyone). Therefore sellers are forced to put their products for the lowest (or close to lowest for high demand items) price. This makes any form of market speculation impossible, and the only source of income a player may have is to farm adena, and this will inevitably lead to hyperinflation (earning adena through farming is an economical equivalent of printing your own money). What was great about early L2 was that in order to exp fast you had to accept a net decrease in adena. Obviously you still could earn by exping w/o ss etc. but not everyone wanted that, which was a great way to get rid of excess adena from the market. That, combined with a "natural" market, where convenience, laziness and product exposure actually were factors, and players could "play" the market and earn money from other players by speculating prices (and therefore wouldn't "print" more money into said market) led to a quite stable economy.