Organizations planning to build their own migration strategy end up being expensive or unviable. Corporates wait to decide on the migration strategy and eventually hurry up, when the existing license is about to expire. Low budget, inadequate resource and improper planning gets added till the last minute. Content migration is a once in a while activity and this can turn up expensive due to lack of expertise.
One of the easiest option is to hire a team of consultant to do this migration. Migrating all versions of content, structure, metadata is key for the success of any Content migration. From Key items to trivial things has to be taken care as contents and its versions represents organic growth of Business. Manual migration is time consuming and error prone when the scope involves large volume of contents. The migrations scope gets mixed up with customization sometimes. It is important to keep the focus on migration when the project is budget and time bound. In these case it is better to do a quick migration and then go for customizations. Moving the customizations to target system is a better choice.
The best way to have a quicker and cost effective strategy is to look for an off-the-shelf products/tools. Migration tools are matured over a period of time, it ensures reliable migration compared to manual migration with less or no error. The tool has to be competent and reliable to handle migration from inventory creation till target system testing. The tool that has stayed over a period of time get augmented in features and fortified to deal complex migration scenarios. By handling complex migrations the tool gets standardized to handle multiple scenarios and larger volumes. Migration tool is the perfect choice if you look for migration to be done on time, within budget and without costly human resources.
If the corporate is sure about environment and software licenses all it takes is a simple tool instead of a full blown migration strategy. The corporate has to pick a tool and do a trial involving their content structures like Articles, Wiki, Blogs, Activities, Files, User mapping, Notes document and Communities etc. to get a real time feel of the migration. This may look like a "Back of the Napkin Migration Model" to pick a tool and why not if it is within budget and time.