My response assumes the 'Formula Column' you are referring to is actually the 'Calculation Column' in the Create Assembly window.

I would use those lines in that column to create an (If) statement calculation for each Item in the assembly. Ex. Does Insurance include Land Value? If YES, what is the value? I would nest (If) statements and formulas to complete the calculation. 

I would use separate Insurance Items in the assembly, each with its own calculations. Perhaps separate Assemblies will be clearer to the user.

Another idea is to create separate Add Ons in the Totals Page for each Insurance. If doing it this way, I would likely base the Add On on a Unique Item Range. Then I could adjust the % to the estimated cost per. 

I suggest you try applying the insurance and warranty costs with the Totals Page addons, as Randy had suggested.  You can assign WBS codes to your line items to allocate back to that code some percentage to add.  It takes a little doing to get subtotals for costs versus sale prices (I assume you use an addon to get to sale price), and to place the addons in the right place.  Use the allocate check box to apply the addons to the line items.

thank you.  I appreciate your response.  The 'directions' are typical of SAGE - not helpful.  I had another user give me some more detail example along the lines of what you describe.  This is a potentially useful column but it is not easy to understand or to use.  It requires several underlying steps to make it function well.  It is not as simple as an Excel  (A3*B14)/2.5  

Yeah I would agree that if you put the Cost of the land on a totals page template this could be accomplished.

Place that add-on the last line of the totals page before the grand total as a Lump sum add-on - and leave blank until you type the value of it in for each particular and applicable estimate.

I would place a subtotal of all above costs before the Value of the land add-on

Next insert below sub-total a Warranty insurance add-on as a percentage of the subtotal just above

Below Warranty insurance place the General Liability insurance add-on as a percentage of the Estimate total

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