Vignettes are mandatory on all motorways in Austria. A 10-day-vignette (the shortest version) costs € 9.20 for cars and € 5.30 for motorcycles in 2019. You can purchase the vignette at almost every fuelling station and motorway service station near the border. Coming from the north, the motorway service station Kiefersfelden is the last option to purchase a vignette.
Advice: if you drive on the interstate, instead of the motorway from the exit Oberaudorf (D) to Kufstein Süd (A), you do NOT need one as yet, and can continue to the Wilder Kaiser region toll-freely. However, city traffic in Kufstein may cause delays.“