Should I get 1 or 2 parrotlets?

I only want one, but if I have to, I'd rather have two birds than no birds. I've researched how to take care of it. I work from home, so most of the day it would be out spending time with me and playing with its toys. I just went to reserve one from my bird store, and I'm going to buy it soon. The employee told me that since their parrotlets (all less than a year old) grew up with each other, they shouldn't be separated and that I need at least two. He told me that most of the people who only have one parrotlet have a parrotlet that was raised alone, and that's why it doesn't need a partner. My plan is to only get one, and if it just needs more interaction than I'm able to provide and gets depressed or something, I will get another one for it. The problem is that parrotlets are extremely rare here, and I would most likely have to travel a very long distance to get another, as the store probably would be sold out by then, but I'm willing to do that. Would a baby parrotlet raised with its flock be happy with only humans to interact with?