Suggested hosting

Hi all,

Having done some CI sites before, I've decided for this current project to use CI again.

This new project will potentially have a lot of users of various kinds.  Not all of course will be online at the time time.  In addition the site will need to support document uploads and downloads of scanned documents.  It will be a web app that we sell to users the services it provides.

There will be need for the site to run some automatic utilities such as scanning a table and sending out "update" emails to expired users.  There will be some date related stuff where a scan will occur and if something has been been done by a date then emails are sent etc.

At first, since this thing has not been sold yet we are probably going to host with a smaller typical host like SiteGround or something fairly inexpensive.

However if this thing goes where we hope it goes we will need much more.   I have little experience in the "much more" category.  I know that we can fire up either VM or static hosts on things like Amazon, but what else is there for high speed, high demand sites?

It seems you go from "shared" to dedicated type hosting.   Are there any great deals, things to stay away from? etc?

The principles of this project are not webadmins and I don't want to do that job either so if this grows we will likely hire a webadmin but I'm hoping we can find a site with some reasonable services built right in.   

Any suggestions, thoughts, ideas?

For the start, the low-end, anyone have any recommendations?  SiteGround ok?

thanks in advance!