If you're strapped for cash, there are some lower-priced alternatives in the OSM ecosystem. https://thunderforest.com/ , for example, has map tiles available in vector and raster forms, and https://www.graphhopper.com/ is a full-featured alternative to the Mapbox routing stack. You can always self-host, too, whether for map rendering or routing or whatever.

(Not to detract from Mapbox, whose product line is amazing and who have some of the smartest engineers out there.)