Obviously, estimating the value of anything you want is a completely subjective matter, because desire is itself subjective. That said, breaking down your motivation into 2 distinct decisions can make it easier for you to choose what you want to do, be or have, more confidently.
Look at WHAT it costs. Does it represent an equitable value equation? Looking at the price of what you want to do, be or have, do you regard that cost as an objectively reasonable exchange for what you’ll get?
Look at HOW you’ll have to pay the price for it. Look at whether or not you are convinced that it is worth you giving up whatever it is going to cost you to pay that price – “Is it worth me giving up 3 annual vacations, a new car, my weekends, my self-respect, 100 hours of my time…?”