How exactly am I supposed to direct the Navi to avoid toll roads, altogether?

 

In case anybody's facing the same issue I was facing, setting the directions preferences to MIN for toll roads will eliminate almost all of them.

In my case, I was interested in avoiding Route 267 around Dulles, which will cost you $7.00 for very little improvement in time. And if somebody's towing your race car behind you, you could end up spending about $100 on the trip just for that little bit of road.

It's just one of those roads that I'd prefer to stay away from. :-)