If a woman in her late 20's (or any age for that matter) is medically diagnosed as infertile due to PCOS, endometriosis, or any number of conditions: how does she go about freezing her eggs if she would like to have children in the future? Whether that be via in vitro fertilization (IVF) or surrogacy?

I imagine that the process of freezing-eggs is different depending on what country you live, your insurance, etc. But I have a few questions:

1: What is the general method of extracting the egg from the ovary?

2: How long can the eggs be frozen to be viable for possible fertilization?

3: Is it better to freeze your eggs younger, rather than older, if you're not ready to start a family just yet?

4: I know this answer will vary drastically, but what is a ballpark estimate of how much it costs to extract and freeze eggs from the ovary?

5: I imagine insurance doesn't cover it, but I'm not certain.