I have at work a jet washer?

I work for a fast-food place doing the cleaning out side and Have a jet-washer its a karcher k4 and now it vibrates and hurts my hands and it leeks water and there is no power in it now its lost power so dose not clean the ketchup of the walls very well now. my boss told his boss the ops consultant and they have said they are going to get a power-full one. what would be the best type of karcher to have for my kind of job? I have see at the car wash big yellow ones on wheels would they be the best karcher to have and would they last a long time?