What's actually going on
You type 20% onto a material line. Then the next one. Then the next.
And there's no setting that stops the client seeing all of them.
This is a really common quoting-software snag, and it's a quick fix. You don't have to master the quoting tool to sort it.
Most quoting screens are built for costing first and showing second. You add a material, the screen wants a quantity and a price, and if you're marking it up, the margin goes onto that line.
The document your client sees is generated from the same list. So by default they see every material, every quantity, and sometimes the maths that got you to your price.
That isn't a flaw you have to live with. It's what happens when one list is asked to do two jobs.
Your internal costing and your client's quote are different documents with different audiences. Treating them as one is what slows you down and overshares your margin.
The smallest fix you can do today
Split the two jobs.
Keep one working sheet: material list, quantities, supplier prices, your markup, as detailed as you like. It's your file for ordering and for timing the job. Nobody but you sees it.
The document the client sees doesn't need one line per material.
Most quoting tools, including MYOB, let you add a line with just a description and an amount, without picking it from an item list. MYOB's own guide says: "If you're quoting for a service, enter a Description and complete the Category, Amount and Tax code / GST code details" (MYOB).
Use two of those lines. "Materials" and "Labour", each with just its total.
If you issue a tax invoice, it still has to show the GST payable. It can be shown as an amount or, when GST is exactly one-eleventh of the total, as the statement "Total price includes GST". Keep the GST code on both summary lines (ATO: tax invoices).
If you're on MYOB AccountRight desktop, you can also add headings and subtotals to group things further. The browser and desktop versions differ, so check your version for what's available.
Your working sheet stays the source of truth. The quote becomes a two-line summary pulled from it, not a rebuild of it.
When it's worth keeping, cleaning, connecting, or converting
Keep what you have if this is a once-a-week problem. Copying two totals across by hand takes a minute and isn't worth touching.
Clean it if you're quoting daily and the margin-typing is genuinely eating time. Same if a client has ever seen a price they shouldn't have. Cleaning means separating the two documents properly, and maybe a formula that pulls your two totals ready to paste. No new software.
Connect it if your costing sheet and your quoting tool could talk to each other. Then the exact two numbers you need come out ready to use and there's no manual addition at all.
Convert is rarely justified for this specific problem. Quoting behaves like this in most tools, and changing software to fix a workflow habit is usually the expensive way to solve a cheap problem.
What "done" looks like
Done means you build a quote without opening a calculator or re-typing a percentage. Your client only ever sees two numbers plus a total.
The test is timing. A twenty-item job should take about as long to quote as a two-item job. The client-facing part no longer scales with the material list.
If bigger jobs still take longer, the split hasn't happened yet. One sheet is still doing both jobs.