s430 remote start

NO!!!!!!!!!

It depends on 4 things.

1. How well do any of the installers at the shop understand electrical theory, immobilizers, and proximity keys(i.e. keys that aren't inserted in the ignition), as well as disassembly of high end cars?

2. How flexible is the customer with time/extra labor costs?

3. Can you get a real human being on the phone(NOT a computerized wiring database) from your alarm/RS manufacturer's tech support department to tell you about the car?

4. Is your shop owner/store manager a corporate weenie who does things by the book and doesn't like non-standard jobs, or is s/he the least bit open to new things?

If answer 1 isn't "pretty well" , answer 2 is "not at all", or answer 4 is "corporate weenie", forget about this job.  You'll be in over your head or wized off from dealing with a customer who can't understand why their $80K orig. MSRP European import is harder to work on than a Geo Metro, or a manager who thinks you're wasting the company's time.

If none of the above, go to number 3 and call your tech support. Most of the wiring databases are written from shop manuals when the cars first come out, and proximity keys are much more common now than in 2000. You may find that they've dealt with an '00 S430 or a similar car since then and just haven't updated their info.

I'd be inclined to go for it personally...you'll make a customer happy(since every other shop has probably told  them 'no' outright) and improve your reputation and the store's, if you can get it done right.