I've heard that from other traders regarding unsettled funds. I never ran into that as Etrade flat outright doesn't allow a trade to go thru if funds aren't settled unless one has a margin account and then there is no settlement period.
I guess I wouldn't be hesitant on buying with the unsettled funds but know that you will have to hold for the 3 days. I wouldn't sell prior to that as that will put you in a position where you may need to deposit funds.
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