I always think in terms of time, and I have a spreadsheet to track my "actual hourly" i get from work and side hustles so I can know which are working best for me. When evaluating items to buy, I think about how much time it would take me to buy the item instead of the amount in dollar or whatever since the dollar's value changes with time. This also helps me because I generally try to not think in USD to begin with since I mostly use Bitcoin. At first, I tried thinking in BTC but it's volatile enough that this is not much any better than thinking in USD. Tying things to hours makes more sense. If you know your "average hourly" it's easy to determine whether or not to fix something yourself or hire somebody else to do it.