The cost for making one birdhouse is $1.50 x 7 = $<<1.5*7=10.50>>10.50.
So the selling price of one birdhouse is $10.50 + $5.50 = $<<10.5+5.5=16>>16.
Thus, Denver will charge Danny $16 x 2 = $<<16*2=32>>32 for the two birdhouses.
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