web project for expert

i plan to build a website where user can create their own store.

referer website
shopify.com
freewebstore.org
highwire.com/features <<< function can be found by creating a trial account and look more deeply
cartloom.com

please answer few questions
which language will u use?will u use framework?how much will it cost and timeline?

requirement
done similar project before.show demo link to the project.

payment will be made by freelancer website by milestone.

serious and professional coder only.