Earlier quoted context omitted.
Just FYI, there's no reason at all to buy the DIY kits over just a regular mini split. The difference is DIY kits come with the lines pre-vacuumed and with seals on the end of them. So when you finally connect everything, the lines don't need a vacuum drawn on them prior to allowing the refrigerant into them. A vacuum pump costs about $100. Just get a regular cheap mini split and vacuum the lines yourself, and save $…
Yeah, vaguely aware that you could diy the entire setup with refrigerant etc. But its not relevant at local prices here in AU. One of the interesting things I noticed here is that manufacturers are providing exchangers and head units that can reuse existing pipes. Makes sense for retrofit/upgrades where running pipes through utility spaces and bulkheads is a significant labor cost.
If I were to have it installed, just about any "professional" will totally overcharge here in the US too.