You have no idea..... MiniSplits are actually relatively inexpensive. Depending on the manufacturer you could have up to 7 zones on a single exterior compressor. Additionally Their SEER ratings are substantially higher, in some cases double. Electricity usage is like half of a window unit....additionally we have one that runs on 3 solar panels...All day. At night it switches over to 220...we could have opted for a battery system for total usage.