If part of the team is remote, then the entire team is remote. Keep this in mind for meetings. If anyone in the meeting is phoning in, then it's best to just keep everyone at their desk and have everyone phone in as if they are remote. Otherwise, the in-house folks just end up tuning out the remote employees and you end up with two meetings. A meeting of the in-house and a meeting of the remotes.
Team bonding is always an issue. Fly people in once or twice a year and really schedule most of their time in-house to be situated around social activities. We do daily stand ups and block out thirty minutes. Wrap up stand up in five minutes, spend the other twenty-five bullshitting about what's going on in your life. When you're not in the office, it can be difficult to really know what's going on in people's lives. If someone has a sick kid, or a grandparent in hospice this isn't going to be readily communicated unless you schedule and encourage some non-work-related conversations.
I find it best to assume that everyone is remote at all times. My experience with the partially remote team was that people in-office would talk face-to-face more often and then would not relay effectively to the rest of the team.
There's still the problem of phone calls having the same effect but we use Slack and Google Docs often enough that most of our conversations are there for everyone to see/search.
Be sure to ask the team what is working for them and if they have any preferences. I find it best for everyone to be up front about these kinds of initiatives. Something that's a minor annoyance can grow into a real problem down the road. Best to lay everything out early and discuss as a unit.
Best of luck! Working remotely is extremely liberating.
Let each team member have a bootable backup drive, preferably it is backed up multiple times a day. You do not want a situation where someone is spending time configuring another machine when his actual machine crashed.
To use the bootable drive, though one needs another machine and giving a backup machine to each team member can get expensive quickly, but the backup machines can have enough configuration to keep moving. But I think it is worth the expense of a basic machine. Eg: I use MBA as a backup machine to my mac mini when working remote and Carbon Copy Cloner to create bootable drive. Become more risk averse and have a bootable drive in the cloud as well. YMMV.