Server migration from freeBSD to Linux

We're a web design firm in Madrid, Spain looking for a 1 time job, but if we're happy it colud evolve in al ong term relation as our server admin and tech person. This is my first project submisission here, so I hope i especify everthing ok. The Mision: We have some clients of us hosted on an old freeBSD server at Verio. We need to move it from there and hosted in another provider which need to be chosen based on location, prices and your technical recomendation. We require Linux + Plesk or similar control panel to manage all virtual host. We look for trustworthy and robust hosting company in a Dedicated Server, however we'd requiere one that will allow us to hire a small server that can be upgraded to more robust one once everything is tested and working fine. We'll provide you links with our options. Tasks: There are 24 sites and about 50 email/ftp user accounts that would need to be created in the new server PLESK or similar, generating the vhost's, DNS entry (?¿) For the user accounts, we'd keep the same user names but generate new passwords. Email aliases and virtmaps have to be generated, to macht what is operative right now . All this sites run on our own CMS programed on MIVA script, so it's ESENTIAL, and this is "key", to install the Miva Empresa vs 3.76 (we'll supply it to you with user manual) on the server so that can run in the PLESK configuration in conjuction with other versions of Miva (miva 5) and other type of scripts that we wish to install in the future. PHP5 and MySQL is a must and have to be installed also. MIVA empresa is the Engine that allows the server to run ".mv" files. Later versions have to be compiled and have a ".mvc" file extension. Once this is done and tested, we'd upload a test site to see that everithing runs well and that there are no scripting problems. If that should occur, we'll need your help to try to fix them. As you see, we look for a 1 time job, but we will be dependable on this person to perform more changes, updates, ssl installations, etc. I hope everthing is clear.