This is custom magento work.
Pallet Module Creation
Preordering process
Notifications
Bilingual site
Multisellers
First part
1) Webkul Marketplace extension configured properly
2) Preorder Pallet module with backend to configure 5 conditions and shipping price
3) Creating worksheet with unique ID and allowing buyers to add items in it.
4) saving/delete/update pallets functionality
5) minimum cases from vendors and max vendors in 1 pallet conditions implemented
Second Part
6) proceed pre-order
7) notification to vendors within 48 hours with 24 hours warning
8) if pallets not accepted or rejected with reasons in a row twice then suspend vendors
9) re-activation vendors
10) notification for buyers to proceed further to complete pallete which is verified by vendors or not fully filled (in case some vendor rejected or did not respond)
Third Part
11) PSD integration to different pages as provided with.
12) 20 points mentioned in PDF covered.
13) Make the site bilingual
14) Sample request functionality
15) Everything else we discussed.