Creating a multisite for a client who already has a website

So I guess I’m looking for guidance or best practices with this post. I’d say about 90% of the WP sites I build are for new clients who have no website whatsoever, so I take them through the hosting & domain process and then I build directly onto their shared server space. Easy peazy!

Lately I’ve been getting some mid-level clients, customers who already have websites up and running and come to me to create cool and sexy new WP sites to bring them to 2012.

So my problem is, I can’t build directly on their shared server cause it’s already being used. Currently building a network/multisite and from what I read you don’t really want to move this type of install from one location to another (so bulding it locally, or on my shared server space and moving it over seems like a bad idea that will only cause heart ache).

So what do you all do? Seems like a silly question, but for the past couple years I’ve built most of my sites from scratch, so I’ve never had this issue before. I’m sure the answer is easy, I just don’t know it. ??

Would appreciate any help/guidance.