For the initial steps of your stitch&glue hull, you will need some kind of a table roughly the same length of your kayak and somewhere between 2 and 3 feet wide. There have been post on this board with builders using old wooden ladders. I think that's a great idea. Once the hull is wired together and your fillets on the inside are done, you could ditch the ladder and just use the sawhorses with some kind of cradles. Add a shelf on each side for tools and supplies. As you can see in the picture, I'm jammed into a fairly small attic workspace, so I chose to have most of the tools and storage areas over-head, and it works very well. The crude cradles that I made are just 3/4" plywood with a rubbery foam stapled on to protect against scratches. I wouldn't make anything very fancy or spend much time/money building the workbench, just start assembling the kit and watch how quickly it becomes a kayak. It's a BLAST!
SMF

PS: I have finished stripping the deck and hope to start the planing/sanding process tonight.