I've been through countless CAD discussions in connection with my other hobby of designing and flying model airplanes and the same things come up time and again.
If you need to actually pay for it out of your own pocket it then by far your one and only cost effective choice is TurboCAD. The 3D abilities have been greatly enhanced from ver 9 and on up. THey are up to 12.0 or 12.2 now and copies of 10 and 11 are easily had for about $30 or even less.
Everyone says get Solidworks or AutoCAD or some of the others but these are folks that obviously don't need to pay for them. Sure these are nice programs but they are priced for industry budgets. TurboCAD can do just as well at most of the tasks but comes with a hobby friendly price tag.
The only other CAD in this hobby category that I've heard of is IntelliCAD but it's not a commonly found one and last I heard the cost was around the $200 mark so it's still a lot more than a non current version of TurboCAD.
But EASY to use? Sorry, that doesn't come with any of the programs. There is a nice 3D tutorial on a two CD package that I've been meaning to get but so far I've managed OK with 2D for my model needs.
I had a "Paintball God" moment once.
Like Al Bundy's Polk High football moment I live on
for the slim chance of repeating that one time
miracle in some small way.........