Have you worked out the offers . Mr . Thou ?   Yes , we have . Here's our CIF quotation sheet . Please have a careful look .   Are the prices on the list firm offers ?   Yes . All the quotations on the list are subject to our final confirmation .   I wonder whether there are any changes in your prices .   All these products are our best-selling lines . The prices of our products will change according to that of the international market demand . And we are always open to negotiate , especially on larger orders . What do you have in mind ?   How long does your offer remain valid ? I need some time to get my supervisors on board with this plan .   I understand . Our offer remains open for 4 days . 