I will create excel spreadsheet with formula or macro

Yes, please send me a simple message asking about the formula. Copy and paste it and give me your end goal. I will give you the result.

Turn around depends heavily on the complexity of the project and iterations. I generally use the quote cost divided by 10 to give a number of days. I can always shorten that time period, but there is a surcharge for expedited work.

Absolutely, my quoting system is as follows. Scope of work is determined and assigned a time value. Some scope is more complex than others and may take more time. Once I have the time, generally given in hours, I apply my hourly rate of $30 to it. This gives a final cost.