Running mutiple XOOPS sites on one server works fine just don't try and use someone like hostmonster they have a limit on their unlimited accounts. Yes I was shocked too I thought unlimited met unlimted. hostmonster has a 50k limit on files ouch (I have over 200k with seven XOOPS sites running) and they do not have many users yet. Most of my XOOPS sites run around 16k. Anyone else having this problem? Any sugestions? I have 14 days to bring my files down or they terminate my account.

wishcraft posted here about multisite. That might help. Another idea might be to change hosts! I can recommend futurehosting.com who I rent a vps from. Very reasonably priced, and no down time to date (almost 3 years). No file limits that I'm aware of (running 5 XOOPS sites there atm).

I'm changing servers, I have no choice, checking several out before I make decision. Then I have six other XOOPS sites I built on hostmonster with their own accounts that I will need to merge off of hostmonster to another server. 50k is very low especially for an unlimited account any decent amount of users is going to put you over that I’m sure. I’ve thought about the multi sites module but there is a lot of hacks that I’m not sure how to do, and even then with a lot of users it is going to put site over 50k. That is why I come here for feedback this is where I’ve learned everything so far.
I love XOOPS CMS

Don't forget to check out the "XOOPS Hosting" forum too.