You should be an experienced PHP and MySQL coder.
Heres some help: Open Source Bitcoin Marketplace Software
Something similar to how Silk Road and Alpha Bay are designed
Since Alphabay has been shut down, it is recommended for the coder to visit another alternative Marketplace TR (TRADEROUTE) to get a look and feel to the recommended functionality.
This will be used for legal transactions.
There should be a possibility for a user to register either as a vendor (sellers account), or a buyer (normal account).
A vendor should be able to upload pictures and info to his items.
There should be an Escrow functionality.
The site should get an adjustable percentage of the finished deals.
There should be an admin panel for maintenance, resolving disputes and support.
There should be a Bitcoin handling mechanism.
It is recommended to run Bitcoind as the client only to connect to blockchain.info.
No blockchain download, no local wallet. 
The suggested architecture is a LAMP-stack, but another sort of arrangement could be possible as long it runs under Linux.
The forum part will be a ready-made forum script and not required to be coded.
There should be four types of access permissions
Administrator: Access to every part of the site.
Support: Access to read and reply to support tickets. Resolving disputes, only access to funds placed in escrow.
User: Access to own account only
Vendor: Access to create lists and sell products.
Vendor Level ranking system (exactly as AlphaBay has)
Become a Vendor, and level up by the same math algorithm Alphabay is using
Categories Possibility to filter and sorting
There should be no captcha on the site. A user should instead be UNIX-like blocked from access after 5 failed login tries for 20 min.
All EXIF data should be removed from JPG's when uploaded to the site. 
The menu and sub-menu items
- Become a seller
- Withdraw to account
+ Possibility to filter
- Domestic -from- -to-
- Shopping cart
- Escrow mode
- New Orders
- Accept Orders
- Sent Orders
- Finished Orders
Private Messages (Encryption GPG)
- New message
- 2-FA GPG - Two-Factor GnuPG for Two-Factor?
- PIN For all user for withdrawing money any user create the pin FIRST TIME WHEN CREATE MEMBER
- Report a problem
Interfaces/Key Features Reference:
Empire Market. : [login to view URL]
You need Tor browser to open it
- Hosted on TOR website, so JScript coding unnecessary (advise me)
- Prerequisites TOR knowledge (anonymity and privacy must be guaranteed)