public String toString() {

      String gasStore = " Name: " + name + " (id: " + id + ")" + "\n\n" +
                        " Address: " + address + "\n" +
                        " Phone: " + phone + "\n" +
                        " Brand: " + brand + "\n" +
                        " Distance: " + distance + " miles\n" +
                        "-----------------------\n";

      if (unlead != null) gasStore += "    Unlead: $ " + unlead + "\n";
      if (plusUnlead != null) gasStore += "    Plus Unlead: $ " + plusUnlead + "\n";
      if (premiumUnlead != null) gasStore += "    Premium Unlead: $ " + premiumUnlead + "\n";
      if (diesel != null) gasStore += "    Diesel: $ " + diesel + "\n";
      gasStore += "-----------------------";

      return gasStore;
  }