We, my wife and I did it twice. Both men one white and the other was black, lived with us as her 2nd husband with full access and use of her. Our cover was the lower level of our home had a separate entrance, with a full bathroom and bedroom that we rented out to assist with the overall cost. Prior to the first full-time 2nd husband there had been others renting/living there so the neighbors became accustomed to people renting the living area.
Each of her 2nd husbands lived with us for around 3 years. Due to career moves each of the men were promoted by their employers and were transferred to the west coast. In the neighborhood and around the local area her appearance with them was a very platonic relationship. When the 3 of us or just my wife and her 2nd husband would travel she would be very outgoing about her involvement with each of these men. GTR