What is "worth"?
I suppose the price-level you can get consistently on the market-place. Sample of 1 doesn't help though.
But, think about what other even remotely comparable new vehicles you can get. Compare their prices with 29k, and maybe you've got your answer.
Edit: Or think about other 3-year old seriously desirable cars (low mileage) that have already had 75% depreciation you can buy with your 30k.
...or buy it and never use it and never make a penny on it, and never enjoy driving it (=stamp collecting).
...or buy it, use it, enjoy it, and watch it's value melt away like an ice-cream in the Sahara to around 10k, if your lucky!
Really a non-starter in my mind, even at 20k.
David