upgrading my virtual infrastructure vmware

Hi,

I currently have a vcenter server running 5.1 and 3 hosts running 5.1

they are in a cluster. I'm upgrading all today

I've already upgraded my vcenter server to 5.5

next step is to upgrade the hosts. I've had failures on my sd cards so I'm going to rebuild the hosts with new esxi 5.5 builds.

I'm going to do it one by one so there is no downtime.

1) Can I take a host down rebuild it and add it to the same cluster?

2) Do I configure the network and storage after or before adding it to the cluster?

3) will all my ha and other configurations stay as I've upgraded the vcenter rather than rebuild it?

Thanks