The Piper Mojave is a later version of the pressurized Navajo. The P-Navajo was known mainly for being short on range and payload. The Mojave was an attempt to resolve those issues. Like any pressurized aircraft, maintenance considerations are greater than one with an ambient pressure cabin. And they should be. From your King Air experience, you know first hand how important systems reliability is, especially at high altitude. The engines on the Mojave are not nearly as reliable as the turbines on the King Air, especially when worked hard at high altitude.

The particular example of the Mojave you referenced, has engines approaching 1000 hours SMOH. Most need a top overhaul at about that time, with some requiring a major overhaul.
I'd plan on at least $50,000.00 each, to major the engines. You'll also need to make an allowance for props in the next 500 hours or so, sooner if the calender limits are about to expire. A very detailed pre-purchase evaluation is definitely in order for any aircraft this complex. Failure to do so may result in you having a terrible experience with your first twin.

I notice you also include some single engine planes in your last list. If you've not done so, I'd seriously evaluate my intended usage prior to making a decision. You may be better served by a good single engine aircraft. Something in a premium quality airframe like a 36 series Bonanza, might be more in keeping with your mission requirements. It's supposed to be an easy upgrade to the Baron, if you decide to later go the twin route.

Good Luck!

DT56