EASY, ADVANCED RIGID WING SAILPLANE
As you can see, a lot of construction parts...
Complicated design and a lot of work before one build it from scratch..
maybe is not worth to continue with design..(or opposite?)

The tail (vertical and horizontal) are build as little wings and can be fold down similar as it is done at hang gliders...
The wing is possible to fold down, but there is also an simpliest option that one just fold the flaps and ailerons.