Consider it as: you're leasing for 24-48 mo. but you're buying it right after that.
Because you're obligated buying it, BMW gives you a better rate than regular lease that the owner may or may not buy at the end of the lease.
I don't know anyone in our forum knows going rate or not but to me, if you're going to buy it, just buy it up front. And if you can't afford it yet, just wait till you can instead of paying a lot more for lease + buy concept. you save some money up front but you'll end up paying a lot more.
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