They keycard will work for the LC. But it's not listed specifically as compatible with Toyota because it's a Lexus part.
Dealers will only say or support as much as what the book states... Some might deviate. But there's not much incentive from a risk stand point for them to deviate.
The card slot is for parking tickets / stubs. But it's big enough to work for the key card if one wanted.
They keycard programming process is the same as a remote. But, as you've experienced, it's a Lexus part so the challenge is find/convince a dealer to program a Lexus part for a Toyota. I imagine you'll get some pushback as they might not understand or want to program the Lexus card to a Toyota.
Here's the part number for a keycard that works with a 2016 LX570. This should work with the 2016 LC. Cheaper than a remote btw.
The LC or the LX isn't special in terms of remotes or keyless entry. Other than the style difference in appearance. Toyota re-uses parts across the board.
89904-50480 - Genuine Lexus TRANSMITTER SUB-ASSY, ELECTRICAL KEY(CARD KEY)
As far as the price you've been quoted.... Perhaps ask the dealer what they would charge if you supplied the parts.
You could order online at a cheaper price and just use the dealer for labor. McGeorge is still making a profit at ~$123.
But most dealers don't do as much volume as others so they shoot for a much higher profit margin. But they need to learn they DO have competition and can't just charge whatever they want. At $400 it seems like they are charging nearly $200 for shop time. That's a little nuts IMHO. Especially when they use the same Tech Stream software we do and it only takes 15-20 minutes....
If they give pushback about the risk of incorrect or faulty parts with supplying your own - they can supply you the exact part numbers.
They couldn't really argue with genuine parts wrapped in Toyota packaging. But they might not be willing since it limits their profit.
Also you might be able to show them the prices you can get parts for online. Maybe they'll budge.
But at that price I would buy the OBD II cable and program myself. Or at-least try. Amazon has a very reasonable return policy if it doesn't work out.
The locksmith you're talking to is giving it to you straight. The "side cut" key machines that can cut by code are about $10k. Most locksmiths don't have the demand to justify. Actually most dealers don't have the key machines either. They order the keys cut from another dealer or distributer based on VIN code. (Keycode btw came with the vehicle during sale on a metal tag - picture below) But that cutting doesn't jack the price that much... Side cut keys are no more secure than traditional top cut keys. They are just different which helps suppliers control the supply.
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