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Need to sell a set of golf clubs? Just go to a FedEx Office.

eBay said Tuesday it has significantly broadened a partnership with FedEx to bring eBay Valet drop-off locations to over 1,600 FedEx Office stores nationwide. The expansion will roll out over the coming months.

eBay Valet lets people hand off their goods to experienced sellers already on eBay to list, sell and ship for them. While Valet has seen some success bringing in new sellers since it launched in 2014, the primary way to get items to experienced sellers has been through the mail. Creating hundreds of drop-off locations in communities around the US could bring in far more stuff and grow the program. That could help eBay fend off a number of startups like OfferUp and Wallapop that are looking to grow in its market.

Also, the eBay-FedEx agreement, while small compared to the size of both companies, offers a potential hint of a tighter relationship between the two as they both struggle with Amazon's aggressive growth. Amazon, the biggest e-commerce company in the world, has been able to rapidly increase its revenue, thanks in part by taking business away from eBay. Meanwhile, Amazon is also ramping up its own shipping and logistics network, as a possible way to reduce its dependence on FedEx and UPS. If eBay and FedEx end up working closer together, it may help them keep Amazon in check.

eBay and FedEx started piloting the Valet drop-off concept in Atlanta and Los Angeles, finding that the majority of customers using the program were new to selling on eBay. Bringing in those new sellers is vital to helping eBay expand its main marketplace business, which has posted weaker sales over the past year.

At the drop-off locations, FedEx employees can offer estimates on how much an item will sell for, and they will package and ship items to eBay Valet processing centers. eBay Valet only accepts certain kinds of items, and the company mentions that the best-selling products include electronics, antiques and collectibles, high-end clothing and shoes, and small appliances. Once an item sells, the seller receives up to 80 percent of the sales price.