I’d advise you to find Mitsubishi Diamond installers and get a few quotes: https://www.mitsubishicomfort.com/find-a-contractor

I’m well north of you, so I don’t have any relevant recommendations unfortunately… And if it was me I’d be installing the system myself anyhow lol. Seriously consider doing a few single-head units over another multi-split. It’ll cost a bit more, but if any part of the system fails you will still have partial heat/cooling, and 1:1 pairings on the units allow each one to operate at full efficiency. Whenever you do a multi-split you lose efficiency for each had you add, and add complexity to your design too. One of those branch boxes is full of connections that could fail and leak refrigerant that would damage your system.