I thought about it when I first moved to town and was contracting here.
I did it once for a friend when I was helping him start his company in upstate NY too though I didnt pay for anything. Its was lovely and peaceful.
My friend knew someone who was selling his boat and that coupled with the slip prices in Mission Bay (and insurance) made it very affordable. I am not sure I investigated everything but the initial cost was not bad.
But I think boat living would get old quick even on the biggest of boats and there are still up keep cost associated with it.
Plus it might be difficult to keep your kid from turning it into a “pleasure boat”. Complete with his own little captian’s hat, ascot, and smoking jacket… I see… Hugh Heffner…
But yeah the numbers work out intitially. That’s all I remember. Sorry no specifics.