Regarding the decision of increasing the number of users, it depends on the organization's choice, whether to opt for CapEx or OpEx. Both options involve expenses over the years. Building an in-house Exchange solution requires investing in hardware, storage, connectivity, and administrative resources. Office 365 shifts the budget solely to OpEx as a subscription service. Scalability is another factor. Starting a new company favors Office 365 due to cost efficiency. As the organization grows, the choice depends on available resources and technical expertise. An internal Exchange setup is feasible with skilled engineers, while Office 365 suits those lacking in-house resources.
