Couldn't disagree strongly enough with the above assertion. They certainly aren't "expensive to work on" any more so than any other plane in the class. They have their quirks, certainly, but nothing that places them above anything else.
I've flown 4 non-obese adults (ie two couples) on 500 NM IFR trips with weekend bags. I've done 900+ NM non-stop solo and wouldn't ever plan to do that with pax for comfort/stretching reasons. My J has a 1025 useful load and with 8.5-9.0 GPH fuel burns that offers a lot of flexibility with loading butts, bags, and fuel to accomplish any particular flight.QUOTE]
Fair enough, but I have long legs and am not all that enamored with sitting shoulder to shoulder. YMMV. I would consider a Mooney if I was flying flat lands mostly alone. I am probably spoiled as most of my traveling has been in a Bo or larger.
As for maintenance, most things are harder on a Mooney than other aircraft because access is tighter. Harder equals more labor. How this varies from model to model a bit, but swapping mags, vacuum pumps, to name a few things, are less fun in a Mooney.