Interested in building a charango? Well, I will not provide a perfect tutorial, but I can present some important steps in building a carved charango, starting with hollowing out a block of wood.
There are charangos made from just one solid block of wood, and there are others made of several pieces. Doing it in several pieces you'll have more control of warping and it's way less waste of precious natural resources, so it's the multi-piece charango I'll go for.
Here is a block of mahogany which will do for the body:
You can use any kind of wood. Maple is a beautiful wood for charangos, chestnut gives it an incredible sonority, and even oak which normally is not considered a tonewood at all is an absolutely first choice for the charango body. Cherry may warp easily, Mahogany, maple and chestnut don not tend much to warp.
The dimensions of the block should exceed the ones of the finished body by one inch in each dimension.
Draw the outlines of the body to the block an roughly saw them out with a band saw or also a hand saw. Sorry, no picture of this step.