While everything So Wonwee said is pretty much standard, you have to look at things by fleet as we have so many and each one is a little different. The main difference with what I experience is the lav, the 400XP is not a good lav, it is internal servicing. Most FBOs have a policy that they will not come into the airplane to get he honey pot for liability reasons so you have a choice of dealing with the smell until you get to a lav friendly FBO or doing it yourself. Its not that bad though, you open the toilet and put a lid on it and then take the tank out (we have a lav kit with goggles, gloves and an apron), the FBO will then clean out the tank. We can tip up to $20 to the line guys for doing it. One good thing about the 400XP is we can usually only do a max of 3 hours and its usually around 1 hours legs so the lav is rarely used, I'd say I have to personally pull the pot out on average once every other month. The key of this is "mileage will very" between fleets, time of year and every other variable you can think of.