Potential Yaris Purchase

[t43er]

Good evening gens, let me introduce myself first. I'm Edmund from Gateshead, UK. Not sure this is the correct place but please move me the correct section if the mod thinks this is against the rule.
I'm about to purchase a 56reg yaris mmt t spirit which had done 16k miles to date. I'm looking for some opinions as I've never own a Yaris before.
Test drive the lovely car just now and must admit that the gear selection will need some time to get used to it. Another thing I noticed is the timing chain seem to be producing some noise. The car has just been serviced 5 days ago so I'm not sure is it normal as it's not picked up during the service.
Also the engine bay looked a bit well dirty and rust (or normal chemical reaction on the aluminium?)
Any opinions would be useful and appreciated. I've attached a couple of photos for viewing.

Regards,
Ed