Originally Posted by John Galt
After you buy an ETF on Vanguard, is there any way to tell what the bid ask spread was?
Is there any way you can minimize this before you buy a stock or ETF?
With Vanguard you might just continuously query for bid/ask prices by asking for real time quotes in another screen after you've placed your order. I'm assuming you've reached the order status screen with your current order and checking to see if it is filled. You can also get quotes (as I recall) if you select the change order screen. Note you do not actually have to change your order to use the screen. I believe you can have multiple screens open at the same time.
Regarding the second question, there are probably many sophisticated strategies for capturing the best price at time of execution. But most of the bid-ask spreads I've seen are in the 1 to 3 cent range. On even a $100k trade that is really not much e.g. $25 on a $40 stock. So is it worth it? On a short term basis you are competing against people & machines that probably have better trading tactics and information.
My way to cope with this is to just get the fastest execution once I've decided to do a trade. If buying in a declining market maybe put in a limit order at the bid or midway between bid/ask. If buying in a rising market just accept the inevitable and put in a limit order at the ask. You will pay the spread in the later case but this beats the occasional time when you wind up chasing the price ever higher before getting an execution.