Steelwork Costing Spreadsheet Upgrade

I need an experienced Excel freelancer to upgrade my existing spreadsheet for costing steelwork and cladding. This will help streamline my workflow and integrate with a Word document via mail merge. Atn the moment I input a lot of information manually but someone with advanced knowledge could create a formula to do the same thing automatically. Most of the criteria is either a maths formula with a what if behind it. There is another spreadsheet that possibly could be added in or connected to it.

Requirements:
- Calculate costs: materials, labour, and plant hire.
- Enter quantities using formulas after inputting criteria.
- Enable mail merge with a linked Word document.

Ideal Skills:
- Advanced Excel skills
- Experience with mail merge
- Strong attention to detail

Please provide a sample of similar work done. I look forward to your proposals!