How to compare subcontractor quotes like for like

You ask three plumbers to price a bathroom. One sends a single number. One sends a page of lines. One sends a number with a note that says "excludes tapware and wall repairs". The totals are $4,450, $4,800 and $5,100. Which is the cheapest?

You cannot tell, and that is the problem. A total only means something when every business priced the same work.

Start by sending the same words to everyone

Most mismatches begin before anyone prices anything. If each business works from its own reading of a phone call or an email, you get three different jobs. The fix is boring and works: write the work down once, as lines with quantities and what is included, and send those same lines to every business.

When everyone prices the same lines, the differences that remain are real differences. One business is cheaper on fixtures. Another is dearer on labour. You can see that, and ask about it.

A line left out is not a saving

The most expensive habit in comparing quotes is treating a blank as zero. A business that leaves a line unpriced, or writes "by others", has not given you a discount. It has handed you a cost you will meet later, usually as a variation, usually at a worse moment.

Flag every line a business left out or marked excluded, and put a figure on it before you compare totals. If the cheapest quote leaves out $900 of work the others included, it is not the cheapest.

Compare line by line, then ask about the gaps

Put the businesses in columns and the lines in rows. Three things are worth looking for.

• Lines nobody could price. Probably the scope was unclear. Fix the wording and ask again.
• One price far from the others. It may be a mistake, a different assumption, or a business that is hungry for work. Ask which.
• Inclusions and exclusions that differ. Same line, different meaning. Settle it in writing before you choose.

Choose, then keep the record

When you pick a business, keep the lines it priced and the answers you got to your questions, next to the price. If the work changes, you will want to point to what was agreed, not to a memory of it.

If you are still pricing the job for a client and have not won it yet, you can still change your mind. A chosen price can be taken back, every business goes back into consideration, and your estimate returns to your own cost until you choose again.

A short checklist

1. Send the same lines, with quantities and inclusions, to every business.
2. Treat unpriced and excluded lines as costs, and price them.
3. Compare line by line before you look at totals.
4. Ask about the biggest gaps in writing.
5. Keep what was agreed with the price.

Novato sends one scope to every business you choose, shows their prices side by side with the gaps flagged, and lets you bring the one you choose into your estimate.