I have to agree with brk. It makes sense to have a server if you need it for internal use (file server, email server, application server) ... but there is rarely a good reason to host your own web apps unless they are extremely specialized (GIS web applications come to mind). You have to deal with firewalls, bandwidth, hackers, etc. The online hosts do all of that for you - they have great bandwidth into their servers, good redundant power systems to minimize outages, and keep their servers patched to protect against hackers. I have a favorite online host, anyone who would like that recommendation can PM me.
Kudos to you for hiring someone to help you work it out. Depending on what you will be doing, my suggestion is to look for someone progressive who is well-versed in web 2.0, online video, and the newer aspects of webhosting. Internet culture is changing and most of the business sites I see aren't keeping up.
Jim Bureau in Alton is a good guy if you're in this area -
cnm@metrocast.net .