Is humour in adverts a good idea?

When I think about comments that advertising experts have made to me over the years, one of the things that comes up time and time again is that everything you include in your copy should add value.

So when I saw this advert from a local agent (actually one I've used to attempt to sell a property myself a few years back), I couldn't help but post it up. (Click the image to view a larger version.)

Much of the advert is quite good - people buy people, so showing team photos is often a nice touch. Perhaps even more so as three of them appear to be family (why aren't they highlighting that?). Also. the contact details are clear and they identify themselves as well established in the area, etc, etc.

So, what on earth is that cartoon for? If anything, isn't the joke a bit off-putting about the properties they're marketing?

I think humour can work well in marketing, but only if it is genuinely funny and not open to misunderstanding. I can't help thinking that these guys might have been better off playing it safe..