With thanks to my blonde friend, for whom this is written. There are pros and cons to everything. I know that. In the case of taking on a lodger this year, I've been able to pay off the mortgage quicker and get in more holidays too. If that were everything, that would be enough in most cases. But there's other positives, for sure, like having someone to come home to when I've been working late. It's even better that the p...