Housing is something that a lot of these apply to.
Food is a more disposable thing and will fall under $20 often so be not worth the time; but sometimes it will be worth the time.
health care can be shopped around for, and you can find experts in the area and information online.
Travel certainly can be shopped around for.
Education is not a physical product; so many of these concepts do not apply (i.e. heavy/​light), there are still several of these that do apply though.
Housing is something that a lot of these apply to.
Food is a more disposable thing and will fall under $20 often so be not worth the time; but sometimes it will be worth the time.
health care can be shopped around for, and you can find experts in the area and information online.
Travel certainly can be shopped around for.
Education is not a physical product; so many of these concepts do not apply (i.e. heavy/​light), there are still several of these that do apply though.