account reviews and billing reviews

ive found with adwords i get a account review right away with a new account then if i raise my budget a day or 2 later i get a 2nd review after that i can keep raising my budget with no review so i take it the first is a overall account review and the 2nd is to do with a higher budget do you know if theres any difference between the 2 reviews would the billing review look for diffrent things to the account review ect?

No. There's algorithms that are triggered and it has nothing to do with hitting certain numbers like $100/day or $500/day. You didn't pass any periodic reviews yet.

I wouldn't say that you're in the clear until at least six months have passed. Adding domains, ads, keywords can also trip an algorithm and cause another periodic review.