Open the slides as needed. No big deal just be careful where you park and some orange cones near slides help. There are some floor plans where you can get to the critical things (fridge and potty) with no slides out. Ours requires one out for fridge and never been a problem on the road. We do trip plan our stops, rest stops, fuel, overnights at walmarts Costco cabellas (some don't allow so call ahead as a part of trip planning), flying j and sometimes an Rv park. Winging it would be scary with the big trailer on.
We don't travel with small kids now but have with my daughter since 6 and our cat. They both still enjoy it and she's 21. Trip planning is done with Google maps and a dedicated GPS unit. Remember if you use google or Apple maps there are places with no cell service so either download maps or get an app like copilot with built in maps or a good garmin GPS that has exit services for exits ahead and teach your partner how to use it before you hit the road.