Don't think of it as much as what is the rate but more like what do you want the rate to be. Right now, interest rates are very closely lumped together - meaning that there is not much of a difference from rate to rate when it comes to price, rebate, etc. It used to be that paying a discount of about 1% dropped your rate about .5% - now 1% in discount can drop it over 1%.
Right now, the lowest rate I see where the discount fee does not get excessive is 4.875%, which costs about 1 discount point or so as of today. If that is the rate you want, then register for it and if rates drop, the discount fee should be reduced. That is probably a better way to play the game sicne you never jeopardize the rate, you just gamble on the closing costs.
If I can be of any help, please let me know.
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