New to leasing. Looks like most people lease a vehicle that is in inventory already?
I would like a GLE 450 that’s configured just the way I like it (looked at an XC60 T6 as well). Is it a bad idea to build a custom configuration to lease rather than taking a vehicle that is on the lot?
Only you can say if it’s a bad idea.
It is a more expensive idea generally.
One can shop the car or shop the deal. There’s a spectrum in between, but if you’re dead set on colors or specific options, you’ll pay a premium for that. You’ll have to determine the value/cost of that premium to you.
In general, GLE deals have been between awful and horrendous, so a custom specced one will only make that worse.
GLE350 quotes have been bad enough, I bet the forum will melt down when they see a well-equipped 450 with minimal discount
I’d expect a well-equipped specimen to fetch a number with 4 digits monthly once normalized for zero drive offs.
My GLE build comes in at $76,145 while my XC60 T8 Inscription comes in at $69,180. Both prices are just based off of what the web pages provide.
I do have A-Plan where the published discount is $4,389 off of MSRP for an XC60 T8 valid till June 1.
I also have the Mercedes-Benz Preferred Employer Program which offers $500 off of MSRP. 
These are both expensive builds. I don’t see the value in MSDs, I can make more cash putting that same amount in my brokerage account than the savings from the lower MF. So with zero down both of these vehicles are close to $900/mo (Volvo) and probably around 1.1k/mo for the MB.
The most reasonable thing to do would be to get a Mazda CX-5 at the highest trim for less than 50k MSRP with a monthly payment below $500 and be done with it …, but the heart wants what the heart wants. 
Post calculator links for these numbers
These are just from the Build & Price tools at the mfg’s web pages. I requested quotes, will post once I get them.
The lease payments. Not the MSRP.
Just for fun here is a quote I received. Bad enough sums it up. Tax is wrong so that throws things a bit. They did admit up front they aren’t the cheapest. Sticker was about $71k
Using A-plan is a great way to overpay on an XC60 by thousands.
You can probably do a lot better than that without A-plan on an XC60. Combine with with the published incentives (which are usually pretty good for T8s) and Costco is going to be a lot better than that GLE 350 quote. $7000 down gives me a throwback to Accord Hybrid.
