On Bisq try posting an offer to buy BTC. You can set the percentage above or below current market price that you’re willing to pay. Post an offer to buy at or just below market price and it’ll get accepted by someone eventually. I’ve bought at/below market price on Bisq. The whole 5-10% premium thing isn’t a thing if you don’t want it to be.

The mempool.space project has a Bisq tab on their website. Go there and look at the latest trades section to confirm. There are trades above market price (these tend to be people putting up offers to sell) and trades below market price (these tend to be people putting up offers to buy).

Try Bisq, it’s not hard and not expensive. There is no Bisq premium when done right.