Usually, you get what you pay for, at least this is true when it comes to supplements. Store bought brands like Walmart, CVS, Walgreens, Target etc are going to have the lowest quality supplements and not only are they probably not going to be effective, they might actually be hurting you. These products have a LOT of fillers and that means a lot of ingredients that aren't useful, or even something you are allergic to. If you are going to run to the store to pick something up, the health food stores like Sprouts and Whole Foods are going to have higher quality brands! I would call these medium level supplements. To get the Pharmaceutical Grade, Medical Grade, or Doctor Grade Supplements, which are going to be the highest quality, you will often have to buy them in a practitioners office or online from the company themselves.
Brands that I sell in my office or have sold in my office that I have looked into and know they are solid supplements:
Supreme Nutrition (Zero Fillers - Hand Packed)
Designs for Health
Dave's Healthy Solutions
Corganics - Relief Cream
Brands that I don't sell, but I still trust:
Boiron - Homeopathy
Dr. Bach - Flower Essence
NOW Foods (Lower Quality, but still decent)
Garden of Life (Was bought by Nestlé in Dec 2017 - not sure how that affects product moving forward.)
Pure Encapusulations (Was bought by Nestlé in Dec 2017 - not sure how that affects product moving forward.)
This list is not exhaustive obviously, but it gives you a good amount of brands to pick from, and a rough general guideline to follow!