Rawai Seafood Market, the Evening Run

You choose the fish. You pay by the kilo. Then you pay again for someone to cook it. If you understand that one sentence, you'll eat well and pay fairly. This guide is the rest.

Rawai, a Sunday, 6:15 p.m. A family of four stand in front of a tray of ice, looking at a tiger prawn the size of a small cucumber. Behind the tray, a woman in a blue apron says "Sawasdee ka" and the price in the same breath. Nobody in the family has heard the price. They're looking at the prawn.

I've done this run on Sunday evenings for years. It's the best-value meal on the island if you play it straight.

Where it is. The Rawai seafood market is on the waterfront by the pier. Stalls sell fresh fish, prawns, squid, crab and shellfish, and a row of restaurants next door will cook what you buy.

How it works.

1. Pick your seafood at a stall.
2. Agree the price per kilo before it's weighed. Not after.
3. Watch it being weighed. In front of you, on a scale you can see.
4. Take it to a cooking restaurant next door. Tell them how you want it.
5. Pay the cooking fee separately. That's the bit that confuses people.
6. Read the bill before you pay. (More on this in our Read the Bill guide.)

Prices move with the catch and the season:

• Fish and squid are usually the cheaper choice per kilo; tiger prawns and crab cost noticeably more.
• Cooking fee: charged on top, per dish or per kilo, depending on the place. Ask which before you hand over the bag.
• Ask the price per kilo and the cooking fee before anything goes on the scale, and you'll know the bill before it arrives.

The four mistakes everyone makes.

• Not asking the price first. Ask once, clearly, in English or by pointing at a number on your phone.
• Accepting a "set bundle." If someone offers a "special mixed tray," ask what's in it and what it weighs. Then compare it to what you'd pick yourself.
• Not watching the scale. The scale is there for a reason. Look at it.
• Ignoring the cooking fee. It's separate, and it's perfectly reasonable. It's only a problem if you didn't know.

What to cook. Ask the restaurant for their suggestions. Grilled fish with salt, steamed fish with lime and chilli, garlic prawns, squid with pepper. Simple preparations let the freshness do the talking.

Don't be shy about haggling gently. A smile and "can you do a little less?" is fine. Aggressive negotiation is not, and it rarely works. The stall owners know their prices. The fairest approach is to ask what's good today, accept the answer and say thank you.

The insider habit. The people who live here don't buy the biggest prawn. They buy the second-biggest, three of them, and ask the restaurant to do garlic and butter. They also ask for the rice before the fish, which is how you know they're local.

Safety and etiquette. Keep your bag on your lap, not on the floor. Don't flash big notes. If you pay by card, check the amount before signing. And if you've been drinking, book a car home. The walk back from the pier is dark.

The honest summary. The Rawai seafood run is simple, delicious and fair if you ask three questions: how much, how heavy, and how much to cook. Ask them all before anything goes on the grill.