public decimal GetTotal()
{
decimal total = 0;
//1. get base cost
total += Desk.BaseCost;
//2. get surface area
total += GetSurfaceCost();
//3. number of drawers
total += GetDrawerCost();
//4. get surface material
total += Desk.SurfaceMaterial.Cost;
//5. rush order days
total += RushOrder.GetCost(Desk);
FinalQuote = total;
return(total);
}