You might want to find a campground that has full hookups for your first trip so that you can refill and dump your fresh water tank a couple of times to get rid of any risidual borax and soap. Some state parks have full hookups, meaning electric, water, and sewer. That would make it easier for you and your wife.
However, remember that RVing is an "adventure." This means things do go wrong, but this happens to everyone, and they are very seldom unrecoverable from. Plus, they provide you with endless stories to tell friends. For example, on my first trip, I had packed flashlights but could not find them. I flushed out the winterizing chemicals from the fresh water tank, and had flushed the two waste tanks, but did not get around to turning on the hot water heater and filling it with water until after dark. I had forgotten to put in a plug on the outside access, and had water running down the side of my motorhome while I frantically went through boxes. I was rescued by a couple of men who did have flashlights and knew how to put the plug in!! I was even able to take a hot shower that night, so all worked out well.
Lesson learned is to ask your camping neighbors for help. Nearly every camper will be more than happy to lend a hand and save you from a disaster!