To ensure you will be getting the required product at the best price it's usually essential to obtain three or more quotations or bids. More importantly these bids need to be adjudicated properly. Part of this adjudication process is to check that the contractor or supplier has:
- allowed for the correct products
- evaluated all the applicable drawings
- priced all the items
- can meet the specifications
- conformed with the delivery or project schedule/program
- complies with the warranty periods
- will meet the required quality standards and documentation
- understands the site specific conditions, as required
- included for all taxes and duties
- allowed for transport as required
- adequate insurance in place
- agreed to the payment terms and conditions
- not incorporated any unsuitable or unacceptable conditions in their tender/quote
- sufficient resources to complete the work in the required time
- allowed for preparing any designs or drawings, as required
It may be pertinent to check on the supplier's/contractor's previous experience and even conduct reference checks with their past customers.
In addition ensure that you have allowed for and added any additional costs that you may incur; such as for additional supervision or facilities and equipment which the contractor hasn't allowed, or travelling to visit their off-site manufacturing facilities.
Finally compare the best price (including the additional costs you may incur), with your budget or allowable. If your budget has been exceeded it may be necessary to revise the budget, look for other suppliers, or even adjust your specifications or scope of work to reduce the price.
(To read more on this subject see 'Successful Construction Project Management - The Practical Guide' and 'Building a Successful Construction Company - The Practical Guide'.)