You could also use a belly band so if he does have an accident it will not go onto the floor. But then you will not be able to pad train. But Anne has given you great advice and if you follow it you will be fine. My Pebbles is still is not fully trained at night and will sometimes get up at night and pee in the kitchen. Yesterday she did just that and I did not see it and slipped and fell. I broke my arm in 3 places and now need surgery.
These little one are very hard to train so please be very consistent.