If he's had regular maintenance done at the dealer it should have a sticker on the timing belt cover that says it was last changed around 180K miles. Might even be an older one for the first change around 90K.
If there's no sticker I'd be wary of the sellers claims of perfect maintenance.
If it was me I'd like to inspect it first when cold so I can open up the rad and check the fluids and then drive it. Let it sit while you check underneath for 10 minutes and then start it again to make sure it starts good with no smoke or other issues.
It's a lot of miles. Look it over good. You've read the buyers guide so you know what to look for.