You need to read the small print carefully (and there can be an awful lot of it) especially regarding completion dates, over-run penalties, quality control and anything else they may care to throw in. Do not be tempted to quote too low, it's much better not to get the job than to win the contract which you may regret big time later on. Allow a decent margin for f**k-ups as nothing ever goes completely to plan.
PS I don't work for Morrisons and I've never been to Gateshead.