Audi owner here. The car does cost more to maintain than our non-German non-luxury cars, but the _frequency_ of maintenance is about the same. In other words, all our cars go in for service at about the same intervals, and get the same work done, but the cost of service is a few hundred dollars higher on our Audi.
It's a much better driving experience, and I like the ergonomics and technology too.. but that's a matter of preferences.
Your issue will be that in this area, they have very few base-level Q5's (Premium trim). Most are Premium Plus or Prestige, due to the market demand here. However, there are over 500 new Q5s in the DC area, so they have a glut of inventory. Audi Bethesda has 107 (!) in inventory. Try there -- they may be desperate.
Here's a way to search all Audis in the DC area:
https://www.audioffers.com/dc/new-inventory/index.htm