How to create a fillable PDF form for construction bidding?

Hi everyone,

I am trying to streamline the procurement and bidding workflow for our business. We frequently deal with multiple contractors and vendors for various construction and IT projects. 

To make the process more efficient, I want to create a standardized, fillable PDF bidding form using Adobe Acrobat Pro that contractors can easily fill out and return. 

Could anyone guide me on the best practices for this? Specifically, I am looking for tips on:
1. How to add dynamic calculation fields (e.g., automatically calculating total costs from itemized rows).
2. The best way to lock certain sections of the PDF so that vendors cannot alter the terms or field labels.
3. Setting up secure digital signature fields for official compliance.

If anyone has a pre-made template or a step by step workflow guide for procurement forms, that would be incredibly helpful!

Thank you in advance for your support.