The original purchase contract stays at $80,000. That number does not change. What you create separately is an assignment agreement, a short document that says you are transferring your rights in that original contract to the new buyer. The assignment agreement is where the $14,000 fee appears explicitly, usually on a line that says something like "assignment fee: $14,000." The end buyer brings $94,000 to closing. The seller gets $80,000, and you get $14,000 from the spread.
So two documents exist side by side: the purchase contract (your deal with the seller, locked at $80,000) and the assignment agreement (your deal with the buyer, showing the fee). The title company or closing attorney sees both and splits the money accordingly.
The thing worth knowing before you need it: some end buyers will ask to see the original purchase contract so they can verify your locked price. That is normal and not a problem, but it means your $14,000 fee is visible to them. If a buyer objects to the size of your fee, that is a negotiation, and some wholesalers handle it by using a double close instead. A double close is two back-to-back transactions where you briefly take title, which keeps your fee private. The Rena wholesaling guide covers both structures under the assignment section in the Guide tab.
One more thing worth confirming with a real estate attorney in your state: a few states now have disclosure rules about what the assignment fee must say and when the seller must be told. That is not something to guess at.
What state are you planning to work in? That changes which rules apply.