Step 1: Identify the Independent Choices
The order consists of four independent parts: Sandwich Type, Bread Type, Size, and Sauces.

• Sandwich Types: 5 options
• Bread Types: 4 options
• Sizes: 2 options (Small or Large)

Step 2: Calculate Sauce Combinations
The customer can add "up to 2" sauces from 6 available. This means they can choose 0, 1, or 2 sauces:
* 0 Sauces: $^6C_0 = 1$ way
* 1 Sauce: $^6C_1 = 6$ ways
* 2 Sauces: $^6C_2 = \frac{6 \times 5}{2 \times 1} = 15$ ways
Total Sauce combinations = $1 + 6 + 15 = 22$.

Step 3: Apply the Fundamental Principle of Counting
Total different ways = $5 \times 4 \times 2 \times 22$
Total = $40 \times 22 = \mathbf{880}$.