You won't need too much help for 99% of the build. I needed assistance for riveting wing skins and some other places that are hard to reach around, flipping/moving the fuselage around, attaching the wings, mounting the engine.
With the quick build RV-8 kit, the only task I couldn't do by myself was closing up the top skin behind the cockpit. I did close the bottom skins of the wings alone, but really should have gotten someone to help me. Other than that, it can all be done alone, given some prior planning and the right tools.
One other thing to remember; building an airplane is a really cool and unique thing! Most of the construction isn't difficult and there are lots of things a less skilled assistant can do. I suspect by the time you need help, you'll have lots of people who are dying to put their hands on it! The real problem is keeping them away from your project and deciding who are the lucky ones that get to hold the bucking bar.
