The point of this procedure is to keep the lane (or lanes) of incoming traffic flowing forward so that guests are spared a long wait time for valet service. This method is usually accomplished by designating one or two of the valets to be "stackers", who simply "push" each car up fifty feet or so and prepare it for a quick "takeaway" for a returning valet to park. The process is then repeated until all cars are parked, utilizing as much lane space as possible, meanwhile keeping the lanes moving. An additional advantage of valet parking, aside from stacking, is that valets can park cars closer and straighter than some customers may park. This will save the space in the parking lot or garage, and prevent the inconvenience of going to different floors by cramming everything in. An efficient valet service will implement (or at least prepare) a system to handle the expected number of cars and guests. This may include, but is not limited to, any of the following: designated greeters, stackers, and parkers, a system for marking car locations, and sometimes even a shuttle service for valets at large venues in order to expedite car return times at the end of the event. Luxury Valet parking also adds a touch of luxury compared to self-parking. Many locations and events that provide valet parking provide extra touches such as bringing the car up front, having the doors opened for the guest, and in rare cases cleaning and detailing of the vehicle. Venues As described above, several different types of venues offer valet parking. These include: Single event: These valets are usually hired for just the evening and have assigned roles for efficiency. Parking may be at an off-site location that can handle many cars and can range from a dirt field to a multi-story parking lot. It might also be in the streets near the pickup location. At a wedding the cars may be stacked in order, respecting the hierarchy of importance of the visitors. For instance, at a Middle Eastern oil company executive party, the vehicles might be stacked in the order of the importance of the executives of the company. Restaurant or bar location: In this setting, parking is usually in the establishment's own lot, but may also be a blocked-off section of a nearby parking house or multilayer lot. Often a dozen spots in front will