Profs who have done a full year sabbatical overseas with a family: How did you make it work?
I've taken two full-year overseas sabbaticals, each on my half-salary plus a small ad-hoc stipend from the host institution, the first with just my wife and the the second with my wife and our two small children.  Fortunately my wife's job is flexible enough to allow for occasional leaves without pay.

We rented out our house (at a slight discount, because the renters also took care of our dog).  We lived like students in a small apartment.  We took public transportation everywhere.  During the second sabbatical, our kids enrolled in the on-campus kindergarten; that was one of the key reasons we went where we did.

We also burned through several thousand dollars in savings and racked up several thousand more in credit card debt, which took a couple of years to pay off, but the experience was worth every penny.  We're looking forward to doing it a third time in a few years, despite the extra complication of older children.

The most important thing I can suggest is to forget the idea of making up your and your wife's missing salaries, or even a significant fraction thereof.  It's just not going to happen.  You just have to live with less and make it work.

The other important thing is that it has to work for your entire family.  No matter how good the experience might be for you professionally, if you aren't visiting a place where your family can actually enjoy living, you are all going to be utterly miserable.  I strongly recommend making connections with the families of your colleagues at your host institution, well before the final planning stages.