What would you do when a friend calls you from out of area and ask you to do something...?

I had a call from a friend who is coming down to visit me for a help. He then said he wanted me to find a lumber store (not one of these Home Center Retail Store Locations), and get a price on a pressure treated post and asked me to call him back. That was 6 pm, Of course the store was closed so I could not get a price. Meantime I asked my friend in town to see if they know a good place to buy lumbers cheap. He told me a place, but he told me to call back my other friend to ask how many he needed, what project he is going to work and how he was going to carry all that weight with his mini van he got, etc basically he was trying to help, and he told me because depend on the volume, the price can change. I could not answer any of his questions... but now do I call back my friend to ask him how many he needs, how he was going to carry them back, and what kind of project he is working on, etc ? or do i just wait to call the lumber and ask them for their price on one lumber ? I feel so dumb, can not think...