Answer:
See below.
Explanation:
We first calculate total costs for the purchase and lease.
Purchase = $3,120 + 600 + (400 * 4) = $5320
Lease cost for 4 years = $1,360 * 4 = $5,440
Differential analysis indicates a $120 more payment when the equipment is leased.
Although this puts the total cost over the 4 years of lease higher than the purchase, it must be noted that lease is annual and a lump sum is not needed where as although the purchase gives you an asset, the savings on tying up the cash in purchase may be able to be used else where more profitably thus a lease seems more viable specially when present value of money would be taken in to account.
Hope that helps.