To purchase a rear roof spoiler for Mercedes GLC X254, you have several options available. 

Online Retailers: Online retailers cater to individual customers and offer a wide range of products with local warehouses for quick shipping. However, prices may be relatively high, and installation can be more troublesome for customers.

Mercedes-Benz Forums or Communities: This is a form of online shopping where car owners with strong hands-on skills buy and install spoilers themselves. However, there may be after-sales issues due to transactions being person-to-person.

Local Auto Parts Stores: While less error-prone, purchasing from local auto parts stores can be the most expensive option. Besides the cost of the spoiler itself, customers must also pay for installation labor hours at auto repair shops.

Online Wholesalers: Online wholesalers target small and medium-sized enterprise sellers and often have minimum order quantity requirements. They can also undertake private customization of automobile exterior parts.

If you're interested in purchasing roof spoilers for the Mercedes GLC X254 in large quantities, Haosheng Car Spoiler Factory is an experienced online wholesaler of car spoilers based in China. We've recently designed and produced the rear spoiler for the w254 model in March 2024. Detailed pictures of their products are available, and if you require a bulk purchase, you can provide your specifications and request a sales quotation from them.