Timing is one of the most critical factors of software size estimation. We need to know quite a bit about the software project to make a meaningful size estimate. However, most of the software estimates should be performed at the beginning of the life cycle, when we do not yet know the problem we are going to solve. In the literature, there are few early size estimation methods. This study demonstrates the results of size estimation methods utilized on a large software intensive military application within the boundary of a project for Request for Proposal (RFP) preparation.