The way you do this doesn't change the monthly payments. For example, if a car lists for $37,500, then, if you subtract the $7500 credit, the residual (50%) would be $15,000. Payments for depreciation over 36 months would be $416.66 (($30,000 - $15,000)/36). If you simply calculate the residual based on MSRP without considering the tax credit, then the residual would be higher at $18,750. In this case the depreciation payment would be $520.83/month (($37,500 - $18,750)/36). However, you'd have $3750 in lease cash which is $104.17/month, which would bring your payment down to .... $416.66.
I don't think that's correct... from how I understand the way you figure out a lease by hand is this...
MSRP: $34,000
Residual: 50%
Money Factor: 0.00040
To figure out depreciation you take selling price of the car - the residual divided by the total months of the lease.
To figure out finance charge you take Capitalized Cost of the car (the amount financed) + the residual all multiplied by the money factor.
In this example the dealer is an ass and won't budge at all from the MSRP. Chevy doesn't offer any rebates and you are broke and don't have any money to pay as down payment.
Full Tax Credit of $7,500 being passed onto the buyer...
Selling price of $26,500 ($34,000 - $7,500 fed tax credit) with a 50% residual leaves the residual at $13,250. Lease terms are 36 months so the monthly payment to just cover their "loss" from depreciation is $368.05 a month (13,250/36)
Finance charge is capitalized cost of $39,750 ($26,500 + $13,250) times the money factor of 0.00040 which equals $15.90/month.
No with no other fees or taxes the total cost per month for the car (which covers the loss in value and the charge to loan you the money) is $383.95/month. Total cost over 36 months is $13,822.20 (ya, the finance company only makes $572.20 off this deal)
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Now with $4,600 of the federal tax credit and the rest going to the finance company.
Selling price of $29,400 ($34,000 - $4,600 fed tax credit) with a 50% residual leaves the residual at $14,700. Lease terms are 36 months so the monthly payment to just cover their "loss" from depreciation is $408.34 a month (14,700/36).
Finance charge is capitalized cost of $44,100 ($29,400 + $14,700) times the money factor of 0.00040 which equals $17.64/month.
No with no other fees or taxes the total cost per month for the car (which covers the loss in value and the charge to loan you the money) is $425.98/month. Total cost over 36 months is $15,335.28 (the finance company only makes $635.04 off this deal PLUS the $2,900 that's left over from the tax credit.)
Now of course, that's taking the tax credit as a dollar to dollar value to the finance company. I'm not certain that's the case but it would be the same with other companies.