With most dealers, website numbers mean nothing. A lot of dealers leave out (read hide) fees and other things they usually tack on from the website price, because they want to make it look attractive. When you call them, the numbers will be very different, a whole bunch of sales folks I talked to don’t even know what’s on their website. Sometimes the car is gone, sometimes they cant honor the number, most often they just go “yeah? that’s what it says? well this is the number I can offer you”
Some dealers (depends on state) have an option to purchase online, or work with third party sites like truecar, honcker etc; they tend to stay with the advertised numbers, but you can almost always get a much better deal than what they advertise.
Email dealers, pick up the phone. Use the website numbers as a very rough guide, but that’s it.
I was looking at those exact same two cars recently. here’s my post with actual dealer numbers Evaluate my lease please: Atlas V6 SEL AWD
The MDX is leasing much better than the atlas right now (by that I mean that a higher MSRP vehicle will work out to a cheaper monthly payment and cheaper total cost over the life of the lease, largely helped by the $8500 incentive Acura is giving out). The Atlas has a lot more space inside though, but is also very plasticky. I ended up going with an XC90 over both of those cars last week.