My situation works out quite nicely, so I'll divulge on the custody, wardrobe and travel arrangements. My daughter's father has moved away twice, the first time 260 miles away, and now 480 miles away. My daughter (age 8) stays with my husband and me during the school year, with her dad visiting at least one weekend a month. If there is a long weekend (according to the school calendar) that is the weekend he visits. She spends six weeks with him in the summer, from the 4th of July until the week before school resumes.
Wardrobe: They're her clothes. If her dad asks me to pack something specific for the weekend, trip or summer, I do it, and the clothes are returned with her. If there is something that she needs when she's with him, he buys it and it gets returned with her. If there is something specific that she wants to bring with her, she brings it. There's no need to duplicate. There IS a need to communicate. Your kids will thank you.
Travel: Her father moved away. Before he moved we discussed how the travel would work. In my eyes, it was his choice to move, so he needs to provide his own transportation or his daughter's transportation in order to fulfill his parenting time with her. He didn't see this as entirely fair, so we compromised. For school year visits, he's responsible for his/her transportation. For the summer stretch, I drive/fly/train her down, stay the weekend, and return home. I drive/fly/train to pick her up. It's the easiest for her. We've had to be flexible in some cases, but above all, it's what's easiest for my daugther.
The simplist situation usually just involves open communication with your child's other parent.