Bulking and cutting

This is going to depend on many factors, so you are going to get a wide range of answers.

Some people bulk for a set time period, they bulk until they reach a certain weight or bodyfat %, or they bulk with the season.

For me, I am on my third bulk. First was 4.5 months, second was 8 months, this one will likely be around 6. I bulk for as long as I need to reach my goals. If I notice my bodyfat% getting too high, or it is getting too close to summer, then yea time to cut. My cuts usually take about half the time of the bulk, generally. Some people cut faster. I cut until I am happy with my bodyfat % and when my physical progress doesn't match with the scale going down (basically, I am just getting too thin, muscles losing shape, stubborn fat not budging..etc)

I like to bulk in the fall/winter.. it is easier to hide the extra weight that way with more clothing, and eating is more prominent which is always fun. Also I don't walk outside as much.

Harder, in terms of bulking vs cutting? For me, bulking is harder. Mentally, physically... knowingly eating more than you need to can be uncomfortable, as well as seeing the scale and weight go up and not being as lean. Also my workouts become more intense.. more frequency, more volume, more pressure on myself because building muscle is so much harder than maintaining it.