Microsoft Store has Forza Motorsport 7 (Xbox One/PC Digital Download) on sale (Xbox Live Gold Required). This title is PlayAnywhere so you pay once and play on both Xbox and PC.
Ultimate Edition $39.99 [microsoft.com]
Deluxe Edition $29.99 [microsoft.com]
Standard Edition $19.99 [microsoft.com]
Prices seem good until Sept 20th.
Note: Before you ask, IMO deluxe only worth it if you tend to buy all the DLCs.