The phrase "negotiating power" refers to a person or group's ability to influence the outcome of a negotiation in their favor. It means having an advantage or leverage in discussions to get what you want. Full definition
It can give you more negotiating power with vendors. (biggerpockets.com)
Additionally, they will come up with an authoritative estimate of the cost of the work, which will give you more negotiating power with your insurance company when settling your final payout. (valuepenguin.com)
With shrinking inventories and more competition, buyers are finding they have less negotiating power in today's market. (ashlieducros.com)