AOU45RLXFZ outdoor unit, 2 7K ceiling cassettes, 1 9K cassette, and an 18K air handler. Installation was pretty easy so long as you are a mechanically inclined person, and are willing to invest around ~$500 in the tools to do the job right. Most of the labor is just basic carpentry and electrical.

The most complicated thing is preparing and flaring the copper tube ends, then pressure testing overnight. R410a is a high pressure refrigerant, the manual has very specific dimensional requirements for the flare to get a good seal. You need to cut the tube end well, then file it it perfectly square and deburr, and use a special orbital flaring tool that costs around $100 to get a flare that meets the required dimensions.

For pressure testing, the manual said to use Nitrogen at the system operating pressure of around ~450 PSI. So you will need to own/beg/borrow/steal a high pressure gas bottle and a regulator. I was too lazy to drive to the airport and borrow my friend's N2 bottle so I used Argon from my TIG welder, it it worked out fine. But yeah, most people do not have a source of 500 PSI inert gas just sitting around. You will also need a vacuum pump and gauge to evacuate the lines, but the compressor comes pre-charged with refrigerant so after evacuating, you just open the valves and start running it, no charging manifold or refrigerant fill needed.

I'm in the Pacific Northwest USA, I purchased from eComfort.com , no financial affiliation. One reason I chose Fujitsu is that all the installation and service data was easily available, but Fujitsu is a REAL pain about selling parts/aftermarket support unless you are licensed distributor. I found a guy through Reddit that I have used to order parts (I broke a thermistor wire by being ham-handed)