Once was a time when I was known for my Hoodoo Review blog, where I reviewed products from various occult shops and botanicas. Eventually I got rid of the blog because I was experiencing too much trouble with inconsistency in products -- that is to say, an item I had loved the first time I bought might not be made the same way when I ordered from the same manufacturer a year later. Sometimes this was due to certain occult shops or practitioners not following a set "recipe" and instead making the formulas however they felt like making them on that occasion. Other times the problem would be a decline in quality (especially from larger makers) as the search for cheapness and easiness overrode the tradition or effectiveness of older more expensive formulas. One example was the Ar-Jax brand of incense, which originally had some herbal matter in the mixture, but over time came to be made with the same plain, colored incense mixture that everything sold by Wisdom Products uses.
In the last ten years or so there's been a big rise in the number of small manufacturers and practitioners selling through places like Etsy and even as Amazon sellers. This can be good, as usually a small-time maker isn't just trying to crank out easy formulas using mass production, and so there is likely to be more care put into their making. The downside is not everyone's recipes are equal, and as stated before, sometimes even the same maker will be inconsistent in the way they make a certain formula.
I do think inexpensive formulas made with artificial fragrances can be just as good as "all natural" types, but over the last decade I've seen a real increase in the cheapness of some botanicas' products. Even back in the "Hoodoo Drug Store" days, pharmacists often cut corners or sold "fake" products as hoodoo mixtures (such as the relabeled popular perfumes from De Laurence), but these days it seems these big sellers don't even think you'll notice the difference when every product they sell is just the exact same thing relabeled.
More and more I don't like to buy from other sellers due to poor quality or inconsistent products. It's increasingly common that I instead use the recipes from my Conjure Cookbook to prepare my own mixtures. Since I make a lot of different formulas, this isn't too impractical for me -- but an individual might need to buy $40 of herbs and oils to make just one formula.
I don't like to make recommendations since you never know when a seller might demonstrate a sudden decline in quality. My best suggestion is to buy from individuals (not companies or brand names) who either offer their own shop or use online markets like Etsy, Ebay, etc to sell their handmade goods.