Give an example of a fairly major purchasing decision you've made in your lifetime. how did you justify the purchase? How did you prepare for it financially once you decided to make the purchase

I bought an apartment with my boyfriend last year because we had been dating for 4 years and he proposed. In order to prepare, we saved up our money, asked the bank for their opinion on the best coarse of action financially, and we tried to decide how much of our savings we should use without being irresponsible. (This is just an example. I am 15 and will be forever alone but yea this is what I would do anyways)