I’ve been using Permethrin for a few years now and it handles all but the nastiest conditions when some Deet is needed on exposed skin. In the spring I spray Permethrin on my fishing shirts, pants, hat and sneakers. I only do it once a year and it seems to last me all summer. The spray can says it’s only good for six weeks or 6 washings so your mileage may vary. I wear long sleeve shirts and pants most of the time when things are buggy. Long sleeve shirts, long pants and a wide brim hat also reduce the amount of sunscreen I need to apply. This combination has served me well without any greasy mess or damage to plastics.
Permethrin is inexpensive so it’s worth a try. Just remember Permethrin is useless when applied to your skin. It must be applied to clothing to be effective. I do occasionally get bites on the back of my hand but not enough to use Deet.
I still carry Deet but I haven’t used it since I started using Permethrin on my clothes.