This has been studied pretty extensively and it turns out that money definitely does buy happiness, but only to a certain point after which you get diminishing returns and eventually no increase in happiness.
It’s been awhile since I’ve looked at the literature, but if memory serves, most people max out on happiness with an upper middle-class income, so probably 3-4 hundred thousand/year for a couple in the US. After that you don’t get any increase in happiness and are actually better off giving any extra money to charities and/or sharing with friends and family.