Question for those familiar with project management

For this assignment a.  explain whether the team should take a macro or a micro approach and justify the approach.  
b.  Identify some factors that could influence the accuracy of the teams estimates.  


Project Resource Management Assignment

The Managed Care Department of the hospital has decided to implement a
Case Management System called Care+. The cost of the software is
$450,000. This includes the cost of the software, software
configuration, conversion of existing data into the software database,
training for 2 people, and on-site resources for 2 days during the
initial installation and go-live. A total number of 12 users will need
training to operate this software. Training time is 2 days per person.
This will be accomplished by the 2 people in-house that are trained by
the vendor. This software system will require the purchase of 3 servers
($1,250 each) that will be configured in a cluster to support the
department's request for redundancy and failover. In addition, backup
software for each server is $1,500. The average salary of an IT worker
is $91/hour. You will need 1 programmer (40 hours), 1 database manager
(65 hours), 1 project analyst (150 hours), 1 operations analyst (20
hours), 1 interface manager (20 hours), and 1 networking analyst (10
hours). The manager of each department has provided you with estimates
of the time required to complete this project. Interim approval for this
project has been granted. You have been named project manager. Senior
leadership would like you to prepare a time-phased budget for final
approval of this project. You will also need to provide a diagram of how
you estimated direct costs, labor costs, and indirect costs. Final
approval will be contingent upon the proposed budget.