this recipe is super cheap, and it *works.*
18 tablets uncoated aspirin, crushed
5 oz. rubbing alcohol
8 tablets uncoated aspirin, crushed
2.5 oz. witch hazel
combine the two solutions. the aspirin will settle a bit, so shake it before use. apply to the bikini area to prevent ingrowns. it can also be used to spot treat blemishes. (aspirin is acetic and salicylic acids.)
another trick that works wonders for the bikini line to prevent ingrowns is unscented roll on deodorant.