99 Camry valve question

I did a search and didn't find anything that specifically addresses my question.

I have a '99 Camry 4 cyl that just turned over 150,000 miles. This car is not abused at all and has never towed anything. I put around 10,000 miles on it per year if I'm lucky and change the oil twice a year and use 100% high quality synthetic oil. Probably 50% of the miles each year are highway miles.

I'm wondering about valve adjustment maintenance for this car. I don't hear any obvious loud ticking or knocking noises coming from under the hood and the car runs like a new one.

Someone told me to not worry about it unless I am hearing loud valve train noise from the engine. But being inexperienced at this I'm not real sure what I am to be listening for.

In a properly tuned and adjusted engine, should I hear any kind of valve noise at cold start up at all? And will slight valve noise dissipate after the engine warms up?

Thanks for your help!

Don't worry about valve adjustment. They should be quiet and not ever need adjusting.