Arguably the simplest way to get the most bang for your buck is to perform a generalized search (such as "benzoyl peroxide acne treatment" instead of a specific product) on whatever online shopping site you prefer to use and sort by "price: low to high." From there, examine the most highly rated items (ideally with at least 20 reviews or so) and you'll be able to sort the good from the bad while staying in a favorable price range.

Of course, it's highly advisable to read those reviews rather than just buying the first thing you see with a high rating and low price. You may discover, for example, that an item which seems like a good buy from the surface has recently had it's formula adjusted, which tends to be a downgrade.

Hmm I'd say there's alot of products that you might use to cook with already that are safe to use on your face.

Items like, olive oil and honey (make sure they're organic and coldpressed for maximum benefits), you can use as masks for your face.
They have antibacterial, antifungal, and anti-inflammatory properties that will help calm down redness and breakouts. 

I love apple cider vinegar too! I use this one as part of my routine: Bragg's Apple cider vinegar- as a toner. But make sure to dilute it before you swipe it on your face. I do a 3 part filtered water to 1 part ACV solution.
This helps encourage cell turnover, so that your pores are not clogged with dirt and dead cells, which contribute to acne.

Drink green tea. 
You can also make tea with lemon and slices of ginger- this helps with digestion and inflammation as well.  Good luck!

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