Told her when he get on he gon' take her to the Galleria
And buy everything but the mannequins, ya dig?
In the previous line he talks about driving up to Dallas and there’s a Galleria mall in Dallas and it’s considered to be one of the most expensive malls in America so when he says buy everything but the mannequins he’s showing her how much money he’s finally made.
The protagonist is from Houston, and the Galleria reference must be that, when he makes it big and becomes rich he will take her to the Galleria in Houston and buy her everything. This makes more sense then going back to Dallas to go to a mall, especially with all of the other Houston references in the song, including “Best thing out of H-town” and taking his momma out of the hood and putting her in the woods, e.g. the Woodlands, a fancy suburb of Houston.
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