Kevin, first the easy part,,an invertor is an electrical device which converts 12v DC to 240v AC.
Now the difficult part,pros and cons of motorhomes.We have had several motorhomes and must say , thouroughly enjoyed them. You have everything you want with you, and dont have to get out if its pouring down with rain, just park up,step into the back,and enjoy.No corner steadies to worry about as you are on 4 wheels, just levelling to sort out.
Disadvantages,,,if you see them as that, not practical for every day use,too many places you cannot get into,like car parks. Not very economical on fuel, as they are about as aerodynamic as a brick and they have a lot of weight to cart around.You have to put EVERYTHING away properly every day before setting off anywhere, which can be a pain. On some sites, if you go out for the day, you may well come back to find your pitch taken by someone else,,always take some string and long pegs to mark your pitch with your van number attached to the string.
Hope this gives you some help,,,its not meant to be totally negative, as we realy did enjoy ours.,but the caravan seemed more economical regarding servicing, no road tax, etc, and the convenience of not having to stow everything all the time we wanted to go out anywhere.