My first thought when reading this was, my son would be picking his teeth up off the floor for talking to me that way. That is one thing I will not stand for. My kids are very spoiled and very lazy, but they do not disrespect me like that. I agree with everyone on here the 18 year old can either get a job and pay up or ship out! No since in him sitting up in your house eating your food, running up you electricity and then being a total ass when you get home!! As for the 16 year old. I am sure there are plenty of way's to get his attention..... take his phone, tv, friends, free tiime, ect. I would go on strike for sure. I would take care of me and dh and they could fin for them self's for a while.....
Goodluck!!