Traditionally, estimating meant using Microsoft Excel to create a spreadsheet on your desktop or server. With the rise of cloud-based tools, today you might use Excel online, which allows you to collaborate with others in an online spreadsheet or Google Sheets which is a similar online tool. Which version you choose will likely depend on your company setup and whether you use Outlook (Microsoft) or Gmail (Google) for your general company email and functions. If you do happen to find any mistakes you can simply go back and edit the drawings and reprocess your file. About estimating, it is done to find out quantity of materials required for a particular project, also rate analysis if done for the same work which needs to be done. Rate analysis includes finding out cost of materials, labours with extra charges which are included in further chapters. The plans is made using AutoCAD, which are given at the end of project in appendix. This plans were made and estimation was done of the building in plan