Buy a surfboard on volume in litres, not on length. Length is a shape decision; volume is the float that determines whether you catch anything. Most intermediate surfers want volume somewhere near a third of their body weight in kilograms, adjusted up for softer waves and down as skill improves. A shortboard listed only as "6ft 2" is missing the number that matters.

Then inspect for water. Press firmly around the fin boxes, the rail line and the nose, feeling for softness under the glass — a repaired ding that still lets water in delaminates the whole board within a season here. Yellowing along one rail usually means it has been stored in the sun and the foam has already gone off.

For dive gear, the service date is the price. A regulator needs a full strip and rebuild roughly every two years or hundred dives, and that service costs a real fraction of a second-hand set. Ask for the last service receipt, check the hoses for cracking at the crimps, and have a dive shop pressure-test anything before you rely on it underwater.