Aloha from windward Oahu! We’re inland just a bit (10 min from the beach) but due to the strong trade winds we get a lot of salt air at our place, and being windward plenty of rain too, so it’s probably pretty similar to Kauai.
I work out of a 10 x 20 carport, which is bigger than what you have to work with, but because it’s open to the wind, rust and dust are my two biggest issues. So I’d say limit the amount of open shelving you have and try to keep things in cabinets if . If you already have shelving (or no space for cabinets) then plastic bins with a good lid will help cut down on dust and salt exposure. You don’t have to go crazy with hermetic sealed plastic bins or anything like that; if you keep your tools clean, and make sure they’re locked up from the elements at the end of the day you are fine.
A few other random thoughts:
- black oxide coatings on steel seem to rust out on me like nobody’s business here. For tools with this kind of finish (usually cheap Harbor Freight tools) oil them and/or store in sealed bags/containers with silica gel packets to keep dry.
- electronic with standard batteries (AAA, AA, 9 volt, etc.) fail all the time here due to salt. I’ve killed radios, remote controls, a digital level, and two label makers this way. The battery acid gets everywhere and kills your valuable stuff. Take batteries out of devices when you are done at the end of the day or pay the price!
- rechargeable devices (18v power tools, rechargeable Bluetooth speaker, that kind of stuff) seem just fine. As long as they are stored out of the elements you are fine.
- as others say, avoid multiple anything. I keep a full set of sockets and wrenches so I don’t cut back too far, but in CA I used to have a “good” set and a few sets as backups, and there just isn’t room for that here.
- A table saw is fine but I’d stick to contractor models that can “get small” when you store them. A good track saw works for most big jobs but you’ll want a small table saw to make cuts on smaller stock accurately and safely.
- Never ever forget about the rust. It’s cruel here. Big table saws and drill presses, any tool with an untreated iron work surface will rust in front of your eyes. It’s worth paying extra for aluminum. Same goes for hardware. Even galvanized stuff does not last long here. Stainless steel (if it works for your project) is money well spent every time.
- weather is awesome all year so you’re right that you can get a lot done outdoors. But make sure you have good mosquito repellent if they are a problem in your area. Also plan on some good sun screen. A pop up canopy for shade and shelter from the rain is also good.
- get ready to pay for shipping, even with the places that say “free shipping” since you won’t qualify. Amazon Prime is your friend for lots of stuff (and sometime the only way to get free shipping) but takes 5 days or more, and some vendors will not ship to HI. You can consider it a “paradise tax” anyone on the mainland would gladly pay in the dead of winter, so it’s worth it.
- Home Depot also has a decent online game, so it’s worth checking there for things your local store does not carry, and usually ships for free too, which is a nice bonus.
Mahalo and good luck. Walking on the beach any time you like, and wearing shorts and slippahs year round is always always worth downsizing your shop for.