Hey @Brick, I know this says ‘fall’ but this older thread has a ton more info in detail plus a video of doing the OAV treatment by one of our members.
Red Hot’s advice to grab the chance to vape before brooding starts is great - OAV is highly effective and causes little disturbance to the bees, without opening the hive and causing heat loss.
I know the heat wands are pricey but at least the oxalic acid is very cheap - so it’s a one-time up front investment that in my mind has many ‘pros’ that outweigh the initial expense. Not giving advice, but I don’t use a respirator - I keep a smoker lit like Bobby does and stay upwind 