I bought some comic books and novels from 2 different stores in Mercari.
The first time, I think I must receive them two times. However, after contacting to Janbox, they said that they have Package Consolidation Service, and I can receive all of them at one time. Well, it is free.
However, Janbox required me to pay in 2 times. Hope they can update for a one-time payment.
They also send regular order status notifications. Highly recommend this. Dedicated service – 5 stars