The option for International Housesitting may just top my list here for the 60 ways you can earn money in retirement.. Mystery shopping caught my attention, as did being a Local Guide. Any time I travel or have friends visit my city, there’s just nothing like a human story-telling perspective to hone in on local stories and historic backgrounds to the area! Growing mushrooms threw me off guard but sounds simple and lucrative. There’s probably literally something for everyone here, and at the very least it’s entertaining to read through.