Training and gooming techniques

Question
I bought a rottweiler mix pup from a local pet store roughly 4 months ago and it has been hell.  My last dog I had was a good dog, but got to big for the apartment so I had to give him up.  My last dog Samson was trained and I didn't have to many headaches with accidents.  The occasional chewing things he shouldn't came up but it wasn't as bad.  My new dog Rocky seem to have a mental block.  The only thing I was able to teach his was sit and when to go to his crate on command at night.  Doing basic household things like going outside to do his daily routine is hard.  He knows to go outside, but he still does it in the house.  Now I know an accident is an accident, but he will urinate or poop in the house, look at me or my wife, and then run to his crate.  I don't know how to fix that issue and the issue with grooming is even worst.  Now my dog doesn't have a long coat, but grooming is difficult because hair is everywhere.  I don't know what type of brush or special product I need to eliminate the hair situation or even minimize it at least.  Please help!!!

Answer
Hi Yul,

Bladder control begins in puppies at 12 weeks. Most puppies younger than 12 weeks cannot physically hold urine or stool for more than a few seconds when they are ready to go. After 12 weeks, bladder control is achieved slowly through the next 3-6 months.

Until your dog is reliably housetrained, he can't have the run of your house. That means when he can't be monitored by you or a family member, he needs to be in his crate.
Keeping the dog on his leash, and attaching the leash to a belt loop is a good way of making sure the dog is always within your sight.

Don't wait for a young puppy to signal you that he needs to go outside. When accidents happen, don't blame the puppy. If you didn't take the puppy outside promptly, the fault is yours, not his. Take your puppy outside upon waking first thing in the morning, after meals, after drinking a lot, after play, after waking from naps, and just before bedtime.

Remove the urge to soil in your home. Clean the areas where your dog has been having accidents with an enzymatic cleaner such as Nature's Miracle.

You didn't say how often you're brushing your puppy. If your dog has short hair, use a soft bristle brush. Brush your puppy daily.

Best of luck,
Patti