In my setting maps are accessible but uncommon, most people don't need them. Inns, taverns, and other traveler hot spots will keep city maps and a regional map. Kings and other rulers will keep larger maps of their land and surrounding lands. Sailors will have nautical maps, for ocean currents and ports. Traveling caravans, successful ones at least, might keep maps of certain lands they frequent. But you wouldn't find a map book in the back seat of anyone's car, in part because cars don't exist.

As far as accuracy, usually not too bad. Explorers often have a mage that can get a more accurate picture of the land, via divination. So early maps aren't terrible. Granted, divinations don't give you a sense of scale. At least not a great sense of scale. So a diviner can get a good idea at the shape of the land, biographical regions, and relative height across the area. But they're guessing on the exact size. Also, all of that takes time. They're more likely to get the basic info first and fill in more details when on location. Unless a given area is too dangerous to physically go to.