Is that 3300 sq ft of Hardie siding or is the house 3300 sq ft? What is it worth to you to not have the filler and dabs of paint? What is the cost of the siding? Labor is most likely a little more intensive for the tabs as well.

"Feels high but I’m not in the business."

You are in the business of paying for the building of a home. For some reason you want Hardie trim tabs. You can accept that price or reject that price or get another another price elsewhere. Does your budget support the price you have been given? A good budget will help in making rational decisions.

Millworkman - the house floor plan is 3300sq ft. Materials are already paid for as is labor for a general install. This is the incremental cost to use the tabs. Relatively small cost for the tabs and then all labor.

Mark- my budget is large, but just as I wouldn’t want pay $200K for an f-150 even though it’s in my budget, I also wouldn’t want to overpay here.

Without knowing the extent of exterior trim required and your climate zone (stainless steel fasteners are required in coastal zones,) it's anybody's guess. I think you'll be better served to ask your builder how he/she arrived at the additional cost.

" the house floor plan is 3300sq ft "

Still no idea on the sq ftg of actual siding. If purchased you should know the quantity, But I am betting that the 5K works out to a buck or two a sq ft. That is the way to judge. If the siding is worth 100k installed (just a wild as guess as there is zero way to know for sure), the 5k for the tabs is an overall drop in the bucket for the look you want. Look at the big picture, not just the 5k. All of which is why I was asking for context.