I use two, one in the bedroom and one in a main part of the house. The bedroom is for sleeping only and the one in the main part is for chilling when needed or keeping them from getting underfoot.
Having the dog in the bedroom with you at night improves the chances of house breaking happening faster, the puppy moving around or whining wakes you up and the pup goes outside. It also usually calms them having you nearby and you avoid a lot of whining and fussing.
Delgado finally at 2 years old earned the right to be out of the crate 24/7. I never assumed that it would take that long but it did, so getting the largest crate keeps the dog comfortable regardless of size and age.
Jasmine - Female Miniature Poodle - born Aug 15, 2010
Loker Delgado Von Stalworth - Male GSD - born Jan 26, 2012
Koda & Zazu - 5 year old male cats
Alex - Male Cocker Spaniel (rescue) - RIP Cuddlebug 2007-2010