1. Nowadays most of the kids from Asia, India,Turkey, Africa and some from europe as well scamming on deepweb.
2. 90% of the store and markets on deepweb are SCAM.
3. Avoid stores, market and vendors who have Whatsapp number for contact (these are mostly kids from Asia or India who have lower class mentality that no one will get scammed if they use their own country phone numbers. Also no legit vendor or market on deepweb in their right mind will use whatsapp for contact.
4. Try to chat up with vendor and markets and sooner or later you will find grammatical mistakes in email, chats or broken english, these poor bastards are mostly from India, Asia or countries like Turkey where english is not the first language, avoid any vendor from these country because they are 100% scammers, and will be happy even if you agreed to pay them $100 for a $800 product or service.
5. Try to haggle with the vendor or market, if they keep lowering the price, or if you ask them to sell $800 product or service for $200 and they agreed, avoid them right away, because no legit vendor or market will want to lose more money on a product or service, only a scammer will want to getaway with whatever they can get from the buyer and runaway.
6. Try to Avoid Onions and markets which got automated payment pages and one bitcoin address listed for all purchases.
7. If you are contacting a vendor on telegram, make sure you contact the correct telegram username, lot of scammers are creating similar looking telegram accounts to scam vendor and market clients, in some cases create telegram groups with vendor name, no legit vendor or market will create a "telegram group", its what a scammer will do.
Example: hacking team has only one telegram: hackngteam , scammers created similar to scam people.

8. Any market with 100s of product and multiple vendors are mostly scam. Example: hacking vendor on marketplaces are scam, real and legit hackers always create their own website and not list their services on a marketplace.
9. Example of common marketplace scams. (in some cases multiple markets created by one same scammer, with fake vendors and products) Example: torbay and darkbay is created by one same loser scammer.
Another example of one scammer creating multiple scam onions and services
http://onion.tor.my/5311/scam-list-indian-african-scammer-you-buy-will-lose-your-money

10. Typical Retarded Asian & Indian Kids Scammers i,e using whatsapp number of europe or good countries then their shithole (india, turkey etc), using word (admin) as username (pathetic)

11. Hacking Services i.e instagram hack, snapchat, whatsapp hack, phone hack, indian scammers are offering for $100-$200 or even less, don't fall into trap, it cost way more to setup a real hack. $50,$100,$200 and between these prices are offered only by low life indian and asian scammers, because even if they scam you for this amount, its too much in their own currency and the slums they are living in.
I will add more to the post after doing more research. leave comments if you know something more.