Why multiply by 23 months and then divide by 24 months for the effective payment? Awesome deal, just curious about the effective payment calculation.
I generally do the total cost (without disposition) divided by the number of months. The LH calculator also adds the disposition fee in the total cost.
Because the 1st mth payment was also rolled in along with fees. So the OP paid just the MSD and all of which will be refunded at end of the lease so he will effectively only pay 23 more payments starting next month.
Hence multiply the remaining 23 months to a monthly of $640 and divide it by 24 which is what the actual term of the lease is.