NOTE : the manufacturer of the kayak recommended against using the handles on the bow and stern for hoisting it (RTFM). Instead it recommended using tie downs about 1/3 of the way down the kayak to spread the load. I put mine at roughly where the thwarts are. If you hoist by the handle over time you could deform your kayak.
Not much to it and I'm sure it's been done before; it cost me about $5 to buy the eye bolts - I could only find 2 7/8" ones (lowes); longer would have probably been better. They were rated for 150# each - so they were complete overkill. I probably have 15-25# of load on each eyebolt. I had 4 older tie downs (lowes) laying around - I only used the clamp end as the nylon webbing wasn't long enough, and I actually had about 50-100' of 1" nylon webbing laying around (ebay). So for me it was $5 out of pocket - I'm guessing it would be about $25 per hoist.
Pretty simple stuff - find studs; pre-drill about 3/4" in. Screw in eye bolt - use screwdriver for leverage. Tie one end of webbing to one eye bolt; loop around kayak on ground, back up to clamp allow plenty extra on the down side. Once hoisted throw extra into kayak.
The higher the hoist, the less impact on lighting.
Added benefits:
- Drops straight down on the truck - no more lifting it up to the roofrack.
Built in work table for working on the kayak.
No more crud under the power boat and I can blow out the garage easily.
I do have issues with a bunch of French clowns trying to get in my garage though.