do we offer sandblasting for White labeling like logos for wholesale? If so how much?

We can offer this.  The price ranges from $10-$50 per piece blasted.  For a standard piece $10-$15 is close

Each piece must be tapped up with the graphic, sanded, peeled and cleaned.

It depends on the product being sanded, as well as the complexities of the graphic.  The more complex, the longer it takes to weed out the part of the graphic that will be sanded.  This takes a lot of human time.

Why is there a hole in my waxmaxer heater?

This is where the wires come through.

If you have a heater like this contact customer service to get a replacement.  You can also fix this at home  to save time as it is easy in this video.