IMPORTANTE:
Too many oil brokers/facilitators/consultants/mandates on LinkedIn are representing scam sellers and don't even know it!
The six key things to watch out for are:
1). How safe the transaction procedure is for both the buyer and the seller.
2). The seller's willingness to reasonably review some terms for a buyer that can still work safely for the seller.
3). The seller's willingness to eventually meet face to face with the buyer in a safe environment.
4). The seller's paper works showing they're licensed to sell whatever, except is cases like OFF-OPEC where you can't get any real documentation.
5). The seller is giving ridiculously low prices for products that are well known to cost much more.
6). If the seller is actually even the end seller.
Talk to your seller and find out if they're willing to provide positive answers to all of these things for any buyer you bring to them and watch their response.
Chances are their grumblings will start immediately and you'd realise you've just saved your self a lot of wasted time and efforts