There are two big questions on the mind of Apple investors, suppliers, and other people that are invested in the financial success of the iPhone.

When Apple comes out with a new, redesigned iPhone with a next-generation OLED screen this fall, what will it cost? And what percentage of iPhones will sport the new design?

UBS analyst Steven Milunovich believes the iPhone 8 will start at $870, and an upgraded model with 256GB of space in this scenario would cost $1,070, he wrote in a note distributed to clients on Monday.

Currently, Apple charges $649 or more for an iPhone 7, and the iPhone 7 Plus costs $769 and up.

Some analysts have previously entertained the possibility that the iPhone 8 could cost $1,000 or more, but under Milunovich’s assumptions, that would be the high-end price, not the starting price.

Milunovich also forecasts that the redesigned iPhone, which is rumored to feature a glass case, wireless charging, and an edge-to-edge screen, will make up 45% of sales next year. Many believe Apple is preparing two updated models of the current iPhone 7 and iPhone 7 Plus in addition to the redesigned iPhone 8.

Last week, I was speaking to a representative of one of Apple's suppliers, and she said one of the big questions they're facing in terms of their business is what percentage of this year's iPhones will be redesigned, and they don't have any specific inside knowledge on that point.

It's important to realize that the marketing and thought process pertaining to any iPhone pricing change is almost certainly one of Apple's most closely guarded secrets - and it's not information that Apple's partners would have any inside knowledge about.

Wall Street analysts don't necessarily have any specific insight on the discussions going on inside Cupertino on Apple's pricing strategy, but they can make educated projections based on what the parts Apple is buying cost and previous years' pricing.

"Assuming that the OLED model constitutes 45% of sales, we estimate the [iPhone average selling price] could be $730 ($783 bull, $664 bear)," Milunovich wrote.

UBS rates Apple as a "buy" and increased its price target to $170 from $165.