When you want some kind of product, you need to do as follow:
Use purchasing steel pipe for example.
1) get price from some kind of Web site,like http://www.worldsteelprices.com/ even if you can not get directly price, but you can see the price for material like HR Coil, CRC coil, GI coil etc. and the add 30-45 usd/ton for process,then that price is an averager price for your need.
2) get price from different supplier, Notice theoretical weght (order by pcs) and Actual weight (by ton), these are much different, Theoretical weight has much more tolerence of thickness than actual weight,theoretical weight usually 7.5-10%.So usually we suggest buyer to choose actual weight, for you can get know the exactly Ton, theoretical weight can not, you only know the pcs, do not know the net weight.
3) Check the supplier buy asking question like how about the grade, usually we say Q345B grade can not do only with small order like only 20MT, So some one say he can give you Q345B welded pipe for only 10MT for MOQ to produce, We think he is just joking. Usually Q195,Q195~Q235 and Q235 it is much easy to produce, but Q235B and Q345B it is hard to find the material with small order, and it is about 60-80USD/ton more than the usual grade.
4) Get to the mill and see the company to assure your product.
5) from talking, Given him some hard question to reply, if he only say yes,sure, without no,sorry.Be careful, usuall he is freshman. Good supplier will give you some choice to choose or ask some question for your need.
6)Looking their certificate, and ask some supplier he has done before.
7) Hearing more and doing slowly.
No gain, no pain. Purchaser has much more Psychological pressure than seller.
More need call me 86-13302063028 or 86-13920276850 Call me Dan Mail: Langegg888@yahoo.cn