Textbook recommendation request: Exercises to supplement Evans and Gariepy

If you look for a generic collection of problems in measure theory and functional analysis, I would highly recommend:

A. Torchinsky, Problems in real and functional analysis. Graduate Studies in Mathematics, 166. American Mathematical Society, Providence, RI, 2015. (MathSciNet review).

This is a great collection of problems with complete solutions.

However, if you are looking more for a collection of problems in geometric measure they and Sobolev spaces, as it is represented in the book by Evans and Gariepy, it is difficult to find one. However, the book

W. P. Ziemer, Weakly Differentiable Functions. Sobolev spaces and functions of bounded variation.. Graduate Texts in Mathematics, 120. Springer-Verlag, New York, 1989. (MathSciNet review).

presents material similar to that in the book by Evans and Gariepy and it includes many exercises. Unfortunately the exercises do not have solutions.

Concerning Geometric measure theory and BV functions, I would recommend Functions of Bounded Variation and Free Discontinuity Problems (by Luigi Ambrosio, Nicola Fusco, and Diego Pallara), Oxford Mathematical Monographs. The first two-three chapters may be of interest to you and they contain (non-trivial) exercises.

Concerning Sobolev spaces, I would also recommend the well known book by Brezis, Functional Analysis, Springer, at least for exercises concerning the one-dimensional case.