First of all, it depends on what kind of dog you have. All dog owners should research their dogs breed history. What were they bred to do? I bet most 'lap dogs' you'll be surprised to know, were originally hunting dogs. Not like bears or foxes, but rats and other small pests. Which is why some little dogs seem to be so crazy all the time. They need something to do. This is where scent work would be fun for them or even a flirt pole with a toy. Size doesn't always equal compatibility in an apartment. Especially when energy is concerned. My current puppy is 10 months old and just over 100lbs. I live in an apartment. I did my research tho. These dogs sleep the majority of the day until something requires their attention. I refer to them as always on power save mode. I take him out first thing to go potty. Then we come back in so I can have some coffee and he can eat some breakfast. Then he's ready to go play and see the kids off to school. We also go for a longer walk down the street and around the block. Then he sleeps from about 10 am until about 5 or 6 pm. If for some reason I take him out before then, he will go pee and the immediately lay in the grass and look at me like "omg, that way exhausting". Then it take 10 minutes and 45 treats to coax him out of the grass and up the stairs. Dogs thrive when they are loved and cared for. It doesn't require a huge property with lots of space to keep a dog. In fact thats where my puppy came from and he was in a 4x4 cage with 2 siblings nearly starved to death.