mixed bag

noun3

1. •
   Any bag containing a mixture of something.

   • a mixed bag of nuts
2. •
   A group of entities with few characteristics in common.

   • The people I met at the support group were a mixed bag: some were grouchy pessimists, and others were cheery do-gooders.
3. •
   Something tending to have both good and bad results or characteristics; something having a mixture of advantages and disadvantages.

   • Owning a car is a mixed bag. It is convenient, but also costly.