I WFH so only have to use a mask for shopping and errands. Yes I understand the cost adds up if you have to wear all day for your work.N95 an KN95 are hard to come by in the USA. Looking at reputable sites, best case I can have a pack of 10 here by the end of February. There are none in local pharmacies. At around $2 a mask that is $10-14 a week/$40+ per month. My understanding with 'single use' is 8-10 hours of wear. So if you have to wear it all day for work that's one mask per day. If you are just using it for shopping and other errands, you can make it last for a while. Even if that wasn't the recommendation, I can't imagine wearing a mask for more than one day...gross inside and out!