Magento marketplace

ModuleBazaar Marketplace extensions are one of the best in market now.

Features available:

Store Owner:

Ability to view, approve, disapprove, update and delete seller requested product.
Set Seller Commissions by fixed or percentage type.
Set commissions for each sellers, products, product type, customer group and category.
Ability to add, approve and disapprove sellers in single click.
Generate Purchase Order and notify seller once the order is placed by customer
Ability to handle simple products, configurable products
Configure vendor public profile view.
Allow different vendors to register and sell their products.
Ability to add, approve and disapprove sellers in one place.
Ability to set global tax of the commission for sellers. Approval Process.
Ability to review customer review and allow the review to be displayed in frontend
Seller:

Responsive Seller Dashboard
Interface to manage profile, inventory, product details, view commission, payment ransactions and etc.
Ability to upload shop logo and add shop URL
Ability to view their orders, invoices, pending dispatches, manifests
Get instant notification about orders, products and payment from admin
Ability to view the history of their payment
Option to update products stock using csv import and export option
The sellers can upload the products along with multiple images via the CSV file upload
Eases the seller's task of uploading large inventory via CSV upload
Buyer:

Option to see the seller's profile
The user can view all the details on the particular product by the seller
Ability to check the availability of stocks of the product from the seller.
Allows customers to give review only if they have purchased product from that seller.

They provide 6 months free support .