I have found the 'B' shop is reasonably priced. You may get a bit cheaper with a big order through some online suppliers, but only for fittings as the delivery charge will skyrocket for pipes. Some other major plumbing chain stores here in Vic charge around 3 times as much for fittings (they only care about their trade customers and milk the walk ins), but their equivalent pipe seems to be better quality PVC (bit thicker, not as brittle) than at the 'B'.
One of our local 'Water Specialists' has reasonable prices and excellent service, and will take back or swap unused fittings, so I don't mind supporting the local and getting great advice. Believe me, you will be in and out many times as you build and have to adjust your original plans, and add on other bits because you saw it in a really cool thread on BYAP...
Make sure you take a good sketch of your plan with you, and be clear in your mind about types of pipes and fittings (stormwater, DWV, pressure, electrical) as they are not necessarily interchangeable and you have to get clever about fitting them together. You also need to revise on the run as you may not be able to get the particular fittings you thought you could. Also, check to make sure fittings have not been put back in the wrong tub on the shelf - I have been caught out a number of times (even when I remember my glasses!)
. It helps to take some small offcuts of the pipes you are using to make sure the fittings fit.There is a good pumps thread here somewhere - search for 'pumps good bad' and it should show up in the list.
Have fun
