1) Contact an Assessor/Auditor. Time varies by organizational commitment strength and availability of resources.
2) Same as 1)
3) You would need to determine the processes required for the organization to operate.
4) Same as 1)
A = have your dedicated resource attend a course for internal assessor and then have he or she do an internal assessment.
B - how do you know? There is a huge difference between "talk" and "talk-walk"
C - more reasons for an assessment
D - in addition to indicating your specific needs for L2, an audit/assessment may indicate the need for a change in head count. Complexity is certainly a factor.
In general, every organization will recruit or collate with a third party auditor (CMMi consultants basically) who will guide through the entire process.
The time for documentation and cost for an organization to be a level 2 will depend on the number of projects your company has....though the projects are not complex and the organization size is small, it may take around 6 months for your organization to be a level 2.
Our company size is 150 with around 12 projects and it took 8 months for us to be a level 3 organization.