Depending on your portfolio, a good rule of thumb for people with high yield investments, is keep your money working for you. Buy what appreciates and lease what depreciates.
In a typical case, a six year loan might run you about $16.50 per thousand borrowed. So, just figure $165 for every $10,000 your loan. A $50,000 loan will cost you almost $800 per month. If taxes and fees come out to about $5000 on such a car, you will either need to put that down, or add it to the finance balance, driving the payment even higher.
If you are one who likes, or needs to turn a car over every 3 years, you will typically have no equity at the end of year 3, on a 6 year note. So while most people may think they are buying, at the end of year 3, they own nothing.
The higher the residual value, generally the lower the payment. So, if you can find an attractive lease, which gives you a payment of $450 per month, as an example, that might be the best way to go.
Do not ever do a 5 or 5 1/2 year lease! I don't care what anyone tells you. It's a bad deal. If you need to do a lease that long to get to your payment, you simply should not be looking at so much car.
joshsquall depreciation must be factored in. The difference between a vehicle's MSRP and residual value can be an indication.