The cars I've bought new and kept 9 years have cost me about 200$ per month in depreciation over the 9 years. The car I bought 3 years old and drove for 6 cost me 200$ per month in depreciation but I didn't get the three best years and there were more repairs. My cars have fewer repairs when it is me taking care of how they are used and maintained for their entire life. YMMV
I bought my tractor new. I didn't want headaches. My buddy said that he would have sold me his old Kubota cheap. I asked him if he meant the Kubota that his wife made him replace because he spent more time working on it than with it. Again, YMMV