Doo...
Just in case you hadn't thought it
through... the flavorings on most extracts will be in either 100% PG ( most typical ) or 100% VG.. so when adding a PG based extract at 20% to say 100% VG base... you end up with 20PG/80VG ... the nic level is also dropped by that 20% so an 8mg nic will then be 6% ( or there abouts ). So obviously, it you'd want a different PG/VG mix, you'd adjust accordingly
Yep Thats all true, so if You plan on using a nic base of lower level or near the level You want. Maybe playing around with a
ejuice calculator before You place an order may be a good idea.
The highest nic level Yimmey offers is 36mg. I would go with that to give you the leeway You may need. And At 36mg it's pretty safe as compared to higher levels i.e. spills & exposure to skin.
I start off with 100mg, cut it to 50mg at 50/50 and mix from there.
But Doo, it seems You have been reading & researching DIYing thats a VERY VERY good thing, You should be able to decide how Yo want to go about it.
And as always and I'm sure You are aware any questions or concerns someone 'round here will help out.