Allow For Inflation

Make sure to allow for inflation in cost estimates.
Particularly allow for large increases in raw material costs (e.g. stainless steel, copper).

This is important in the tender preparation process. You don’t want to offer a fixed price and find that your material costs go up dramatically.

It is common to put a clause in your contract/offer conditions that allow for price increases on certain parts of your work if the material costs increase above a set percentage.