Tesla pricing seems to be flat rate ($W for 1st unit install with surface conduit, $X upcharge for hidden conduit, $Y/ft for softscape trenching, $Z for a second unit, etc). How that compares to other pricing depends on what work that 'other' pricing is going to deliver. Having gotten multiple bids here in Phoenix, I can confirm that Tesla's pricing is more expensive than those doing the 'basic' work but is much less expensive than those quoting the 'same high-end' work that is the only thing Tesla will do. Tesla's onsite review doesn't seem to be so much about pricing, but to get the exact info so the install can be done right the first time.
For that flat rate, Tesla's installation methods are the "gold standard", not the "code minimum". Case in point: For a 50-amp breaker where all the wiring is hidden within walls and attic crawlspace, some will quote 6/3 or 8/3 NB-B cable run thru the wall and attic cavities, meet code, and be less expensive. I also had 4/3 NB-B and 2-2-2 SER cable quoted me by various electricians (yes, I got a lot of different quotes and learned a great deal in the process). Tesla was the only company proposing THHN-2 individual wires being run inside 1" EMT. When I asked other installers (who came after Tesla's reps) to quote that, the consensus was that such an install would be 'gold standard' but probably "too expensive" so they didn't want to quote it. Tesla, meanwhile, was measuring out "This we can hand-bend onsite, but for each of these other pieces we'll have the factory machine-bender exactly these curves to spec in advance."
The quotes for the work to upgrade the wiring from the main panel to the subpanel were particularly interesting. Tesla quoted a fixed price based on the trenching thru <x> feet of softscape and <y> feet of hardscape, with the upgraded subpanel and connect into the main panel. Others here quoted a lot of "maybe if we run some visible conduit here" and "if we try to run it thru that stucco section hopefully it'll work and there won't be a firestop in the way", and came up with quotes much lower than Tesla's. Only one other was willing to trench to have the conduit properly buried and completely hidden, and their quote started out a bit higher than Tesla's, *plus* their quote came with a disclaimer that "and after we're gone you'll need to separately pay several hundred to repair the concrete walkway, the brick fascia, etc" which would have added many hundreds more. So again, the 'other' quotes offering lesser work were significantly less expensive, but the quotes for the 'same high-end' work were actually much more than Tesla's quote.
Bottom line: Every install is unique, and every owner's goal / budget / interest is unique. If you have a simple install and your goal is a "budget install that meets code minimums", there is nothing wrong with that and you can probably find a local electrician who will provide that. Heck, if it's a really simple install and you're handy, perhaps you can do it yourself for parts + your time + inspection fee. Then again, if you have a complex install and your goal is a "gold standard install that looks beautiful, is exactly where you want the charger, and elicits not just approval but respect from your local code inspector", then Tesla's quote will likely be lower than others. Just make sure to understand the pros and cons of each installer's approach before signing. FWIW, my choice is Tesla.
(NOTE: Things may be different elsewhere, Tesla may have changed things, YMMV, insert other disclaimers here, etc).
