You are asking about installing these things on a linux server and your company offers webhosting so that leaves me to wonder about the quality of the webhosting and the ability to fix any problems.
Also on your site all the files are .html so i hope you dont plan on making any changes soon to every page. you should make some includes in php to include the content on every page it also saves space.
And since you dont use .html on your I dont think you are using a database so I believe you may have troubles admining databases for all your clients.