Ben, if you buy a truck right, say an Avalanche within 400 of invoice (not hard to do on most vehicles), get the 3500 rebate plus the 1K bonus cache, skip the dealer F&I and got to your bank and get 4-4.5% for 48 months and BUY it, you will do better trading it in at 3 years for something NEW then by leasing. The trick is that getting the $4500 in rebates, throwing some downstroke, and taking advantage of 4% financing, you're payment will be close to that of a lease unless the vehicle has a high residual value (high lease residual vehicles do not make good "Sand Sleds"
). After 3 years with one year left you flip it into a new car. If you lease you are not getting all the incentives and the cheap rate financing available now (auto leases typicaly won't disclose their internalized rates or what you are buying the car for and they get to cushion their bottom line as you negotiate payment and not "buy" price). So at the end of 3 years or so you pay 2K+ in overmileage fees plus any dents, nicks, tires, and scratches, then you need to come up with another 2-3K downstroke and start the entire lease process over again on a different vehicle.
Trust me, leasing is not a good fit for you. Buying is. If you were getting a car to drive 15 miles round trip per day to the commuter rail and once a month to the mom-in-law's house leasing would be OK. You are not a good lease candidate.