Their accuracy depends on a range of factors. Think of them more as an indicator than as a precise measurement. If the majority of the deck reads one thing, but a particular area varies from that a great deal, it can indicate a problem area.
Don’t worry too much about “tightening” deck hardware. If hardware is leaking, it’s more often an issue of failed sealant- which is all but guaranteed after decades in service
. If anything is showing obvious signs of leaking, tackle those times first, then you can make your way around the deck as you find the time and rebed things. Plenty of books
and tutorials available to walk you through the process. The hardest part is usually accessing the nuts that secure the hardware in the cabin
It’s not a unique failure with the boat your looking at, and it doesn’t sound like the integrity of the boat is compromised. You can always use that to try to negotiate a little extra money
off the purchase price
, but don’t be too worried if they don’t bite on that.