Thinking about a DIY mini split? These systems come with pre-charged R-454B...

https://smart-wiki.win/index.php/Is_a_9,000_BTU_115V_Mini_Split_Enough_for_a_Bedroom_Office_Combo%3F

Thinking about a DIY mini split? These systems come with pre-charged R-454B quick-connect linesets, so you skip the vacuum pump and avoid needing an EPA Section 608 license