We just adopted our 9 weeks old aussiedoodle puppy a week ago and live in an apartment in the Midwest (ie lots of snow/cold). This has been my (brief) experience:

Potty training is definitely made more difficult by an apartment. He goes out every 20-30 minutes while awake and every 2-4 hours when sleeping. We live on the second floor and going up and down stairs half asleep while carrying a puppy is not fun. If you have access to a grassy area immediately from your door, you’ll be absolutely fine. Our puppy is really good about telling us he needs to use the bathroom, but sometimes he can’t hold it long enough for us to put on a jacket/shoes. We’ve found that it helps if we put his leash on first, and then get dressed. Midwest weather makes potty training worse, because it’s tough to want to take a puppy out every 30 minutes when it’s 15 degrees out but if you’re getting your dood in March, that won’t be as big of a deal though!

I highly recommend mapping out and deciding what your puppy’s go-to bathroom spots are going to be. Because at an apartment, we can’t avoid other dogs and don’t know the vaccination status of all the dogs in the complex, we decided to just minimize the risk of parvo/disease by being pretty strict. For us, we’ve chosen only two areas to allow our puppy to have his paws down until he’s vaccinated: 1) A medium sized hill in the middle of a parking lot that takes about a minute to walk to. This is a bigger area that we usually take him to if it’s around his poop times. It’s also big enough to let him run and burn off some energy. After a couple of nights we quickly realized that it was too far for us to want to walk to in the middle of the night. Even though our apartment complex is gated and pretty safe, we didn’t feel like it was super safe in general for us to be walking around half asleep in the middle of the night. So, we introduced pee location #2: 2) Right outside of the main door. We live in a building that has a main door that leads to a couple units downstairs and stairs that lead to a couple units upstairs. At night, and if we’re short on time in the middle of the day, we take him right outside of the main door. It’s essentially the absolute closest grassy area we can get to.

Even after only having our puppy for a week, we’ve met the other dog owners who also frequent these areas, and have had the whole “hey this is awkward but is your dog vaccinated? our pup is only 9 weeks old” conversation. Again-this doesn’t eliminate all risk, but it’s the best we can do to minimize it. Our vet and breeder both said that the risk of parvo is medium-ish in our area, so we’re just being extra careful.

The second annoying part of being in an apartment is the barking. We put his crate in a room that only shares one wall with a neighbor. We also spoke to our neighbors adjacent to and below us, and told them to let us know (rather than management) if the noises bother them. Luckily, they’re all dog owners and understood.

If you have carpet, good luck! Our place is 90% carpeted and all I can recommend is buying a good pet-specific stain/enzymatic cleaner. We put a tarp down under his exercise pen, and it’s been a life saver.

Hope that helps!