When I housetrained Beenie and Frankie, I had them tethered to me with a leash at all times. Once an hour, I'd take them out and after they did business outside I'd make a big deal about it and squeal and give small treat. Over time, increase time to 2 hours then 3 then 4 etc...

When a mess happens in the house and you catch them WHILE THEY DO IT, you scold: BAD DOG in firm voice and take him outside to finish.

Mickey just doesn't know where to go yet... that's all. It's a new house.
Also, is he neutered... he may be trying to make the house smell like him since it's a new place. Males that are not neutered tend to do this more.