Mini splits are air source heat pumps.
I have not installed one personally but most require special tooling ( vacuum pump) some places its actually illegal unless your a licensed HVAC person to turn the refrigerate valve on. That said you could do 90% of the work yourself and hire a HVAC contractor to do the last 10%. Or hope the HVAC police don't show up at your house. The more expensive units usually void the warranty if you install yourself.
YouTube has lots of videos on the installs.