The distinctions between needs and wants will be different for everyone, but once you have your list, it makes sense to
match essential expenses with guaranteed income — money that you can't outlive — like Social Security, pensions, and lifetime annuities (which let you convert savings into guaranteed income).
Volunteering with those organizations highlights not only the
expense involved in preparing them for adoption (vet checks, vaccinations, spay / neuters, often other health problems, food, physical care, transport, etc etc etc), but also highlights how
essential it is to make a good
match for the dog - and that means getting to know the applicants carefully and choosing the best
match.