Obviously not a GC here BUT- we do large scope TI’s with a ton of variation.
Our process is simple.
We’ve taken the time to figure out what an one-off call out for a specific part of the job would cost at our target margin. Over the course of several projects we’ve built up a solid list of rotating line items.
The line items are professionally written and basic enough that minor adjustments can be made if needed to add to the specificity of the project.
Each line item takes into account our hourly and labor with mark up. (Flat rate- but you know)
With that- when we quote jobs I can literally just walk down the scope and select my line items- select my quantities and send it.
With GC work it’s way more scope and variation but that’s worked for us. You could also try working one out the normal way and then take that same plan and upload it to ChatGPT and prompt it by saying: “I need you to estimate this from the position of a Pro GC Estimator, my hourly rate goal is (fill in the blank), parts mark up is (fill in the blank).” And upload that with the file.
See how accurate and how close it gets to yours.
Best of luck!
-Stephen Jobe
