I recommend to move this thread to Micro Earnings board. There you will get answers faster than on Beginners board.
1. I only tried 2 networks to buy advertisements (a-ads and mellowads) and they don't gave invoice. But there are some networks which are working both with Bitcoin and fiat, maybe it would be possible to ask for invoice there.
2. I never tried to follow, how much it takes to update adverticing price when Bitcoin goes up. But as I remember, some networks have fixed prices in $, so it's always updated in BTC value.