The price of a 4x8 aluminum sheet can vary depending on a number of factors such as the thickness of the sheet, the alloy used, the supplier, and the location. In addition, aluminum prices may fluctuate based on market conditions and other economic factors.
To get accurate prices for 4x8 aluminum panels, you may want to contact a local supplier or check out an online store that sells aluminum panels. Estimates range from $100 to $200 for a 4x8 of 0.125" thick aluminum, but could be more or less depending on the factors above.
If you want to wholesale, you can contact international aluminum sheet manufacturers, they will provide tons of price, the price will be much cheaper.