Installed cost of a 24000 BTU 4-unit mini-split systm

Greetings! I just had an estimate for a 24000 BTU 4-unit mini-split Carrier system. I have a 900 Sq ft ranch--with a complete 900 sq ft semi-finsished basement. 3 units would go on the main floor (one in each of 2 bedrooms and one in the dining room/kitchen area that opens into the living room), ond one in the basement. The price quated is near $9000. This seems high by at least a factor of 2 in nearly everything I've been able to glean on-line. I just had solar installed and this would likely pay for running the system. How does this price seem to any of you here that has experience with these systems? TIA