[turtlebits]

Part of the problem is that buying refrigerant requires a certification/license.

Also in Seattle, only an HVAC company can pull a permit for refrigeration, even though plenty of heat pumps/mini splits are pre-charged and you'll never need to touch refrigerant.

[sokoloff]

The EPA 608 universal takes about 90-120 minutes online and is free at SkillCat (no affiliation, but I tossed them $50 as a thanks). The 609 (for autos) takes way less time but costs $25 online.

I’ve bought refrigerants online several times over the years without showing any license (even though I hold an EPA 608 and 609). It’s legal to buy for resale, which is probably how suppliers get around checking.