How long a quote should hold
A quoted price needs a validity period, both for the provider and for you. Thirty to sixty days is common and sensible: long enough to run a comparison and make a decision, short enough that a provider is not committing to costs they cannot predict. If a decision is going to take longer, say so and ask whether the price will be held, rather than assuming it and being surprised.
After award, the useful concept is a review date rather than an expiry. An annual review date gives both parties a scheduled point to look at the arrangement, which is far healthier than a price that either never changes or changes without warning. Put the date in the scope so it happens, and use it to review the schedule as well as the figure. Treat the review as a scheduled event rather than something raised only when one party is unhappy.
