Nancy - Well, I also agree with the three Steve's and a Bradley. A Site is for data separation and an organization is for data sharing. Look at the main objects which are set at the Site level which you can do in Database Configuration and ask yourself the question does it make sense for this data to be separated, one facility from another. If the answer is generally yes, then each facility should be in its own site.
Making the decision about Org and Site structures can be easy and sometimes very difficult. It can require a lot of background knowledge of the business and a bit of forward thinking. The terms you used "security groups, warehouse, work orders, etc" point strongly to one facility = one site, but you used the term etc, which just might point in another direction, but my guess is it will not.
Remember a user has one Default Insert Site (in their profile). They would not thank you if data were being entered centrally and retrospectively and they need to keep on changing their profile.
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Andrew Jeffery
Maximo SME
ZNAPZ b.v
Barnstaple
0777 1847873
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