Classifieds Marketplace

Sorry If this has already been asked, I did a search and could not find anything related. 

I am looking to create an online classifieds marketplace site and am at a loss as to which is the best software to go with. I have literally spent hundreds of hours and feel like I am not making much progress, as such I decided to post and see if anyone with experience would be able to help me out. My budget is not very large as this is for a startup business. I am looking to accomplish the following:

Sellers can list their items for sale by uploading pictures and descriptions of their goods. Sellers will setup an account and list their items for free, however agree to pay a commission to the site admin once the item sells (I.E. 20 percent for clothing, 10 percent for everything else).

Buyers will browse the site by location and find items they would like to purchase. They can message the sellers directly with any questions they have. There will also be an offers button so the buyer can submit an offer that will send an alert to the seller. The seller can then review the offer and either accept it, or provide a counter offer. Once the buyer and seller agree to a price, the buyer can add the item to the cart for purchase. The buyer is able to add many items to the cart, from multiple sellers, and pay for all items with a single checkout.

Payments will be handled online with Stripe, where the funds will be split between the site admin and the seller (site admin will get the commission and the seller gets the rest).

Once payment is made, the buyer will pick up the item from the seller.

The site would be very similar to however with the added shopping cart and the seller having to pay a commission when the item sells.

Thanks in advance, any and all help is appreciated.