Pocodot,
My example before was the different temperatures that can be used for NY style pizza. That's just one style. If you get into other styles, pizza can be baked at anywhere from 450 to 900.
Now I'm guessing that your friend implied that to make 'his' pizza, you'd need 650 deg. But that's only with
his oven, not your oven. With the right oven setup, you bake his pizza at as low as 525. That's the magic of materials science. You can take a home oven that may only go to 550 and bake the exact same pizza that a pro is baking at 650.
Don't get too caught up with 'target temps.' It's all very relative. Also, this may not be the reason you're deciding to build a wood fired oven (WFO), but, just in case it is, don't buy into the concept that, in order to make great pizza, you have to own a WFO. WFOs are great for entertaining and for making one particular style of pizza (Neapolitan) at high temperatures (850ish hearth, 1000ish ceiling), but for other styles, they're not essential. The favorite pizzerias in your profile produce a pizza that's very achievable in most home ovens with the right set up.
Don't get me wrong, I'm not trying to dissuade you from building a WFO- it's a great idea. It's just that if you think you have to wait to make pizza until you've built it, especially the kind of pizza you enjoy, you don't. In theory, with a little homework and stone shopping, you could be making those pizzas (and better) within the week.
As far as help building your WFO, we have some members here who have built their own WFO and may answer questions that you pose, but if you really want to go where the experts are, I suggest taking a look at
www.fornobravo.com. Their forum has a vast amount of information- and, for building a WFO, you need all the info you can get.
But, in the meantime, let's get you making pizza. Tell me about your home oven. Peak temp? What kind of flours do you have access to? Do you have high gluten bread flour at your disposal?