In the end- and despite all odds- the Hobbs family vacation is a success. The family's immediate problems have been ironed out- mostly by an exasperated Mr Hobbs- and everyone has become closer... their formerly hostile grandson even cries when he has to leave his grandparents. They return home healthy and happy, even if Mr. Hobbs privately believes that a little vacation goes a long way.
The ongoing house/plumbing issues provide a few laughs and come into play later on in the film (ie. the scene with the Turners) and also give us a call back to It's A Wonderful Life: when Mr. Hobbs starts up the stairs, the knob from the newel post comes off in his hand.
So to sum up, Mr. Hobbs Takes A Vacation is better than I thought it would be, affording me a number of genuine laughs. These were however mostly due to James Stewart's performance of the material rather than the material itself which is pretty standard fare for the time period, and frequently uneven. There are some great character actors in the film- as well as Stewart and the always excellent O'Hara- and they make the movie better than it should be. All in all, not a stellar movie, but a pleasant enough way to waste a couple of hours.