Prep It Pack It Ship It is a California-based company that offers inspection, labeling, bundling, packaging, and shipping exclusively for Amazon FBA sellers. 24 to 48-hour turnaround is standard.
They also offer additional services such as product photography and have the facility for sellers to store their inventory.
Pricing depends on service level including labeling, packaging and bundling.
No membership or monthly fee.
See the website for full pricing information.