I’m one of the people who said it costs more to lease than buy. Let’s look at your 03 Infiniti QX4 and your 05 Cadillac CTS. Let’s say you already owned the BMW (maybe you’d saved your money in the past instead of leasing cars you said yourself you can’t afford to buy by getting a less expensive used car), so you trade it in and buy the QX4, which you trade in and buy the CTS.
If you had bought it outright, the Infiniti would have cost about $35,000, and your BMW would have gotten you a trade-in of maybe $22,000 (Edmunds doesn’t show a 525 for 2000, so I went with the 528 and estimated depreciation), so you would have been making payments of $700 a month with taxes and interest on a 2-year loan and you would have owned the car when you got your CTS. On the CTS purchase of about $31,000, your QX4 would have netted you maybe $23,000 on your trade in. Plus taxes and interest, that 3-year loan would have only have cost you $320 a month.
I used a lease calculator to estimate your lease costs on the Infiniti, which were about $700 a month. Okay, so you were even there because keeping the car for only two years means you lose a lot to depreciation initially. But with no equity in the car, you start over from scratch with the CTS. The monthly payment on that lease? About $530, which amounts to about $8,000 more you paid over the last three years than if you’d bought your cars.
I don’t see how high monthly costs from a lease put you ahead, and with my way you still get the same new cars each time. But hey, if you’ve got money to burn, who am I to tell you not to?