kayak cart - mine's more of a pain in the neck than it's worth to use - I used it when I had a 70 lb tandem that I couldn't carry on my shoulder. If you can't carry your boat on your shoulder, then get a kayak cart

I have one of these:
http://www.amazon.com/InStep-17-CC40.../dp/B001HCITHG

If the wheels get stuck on something, the kayak tends to topple off of it - then I have to go back and put it back on it, etc. etc.

I do tend to park as close to the water as I can - but I can carry up to a 60 lb kayak or so on my shoulder for a reasonable distance.