if I am going to do it at all

I buy good ingredients.

私は良い材料を買います

If I am going to buy at all, I buy good ingredients.

私はどうせなら良い材料を買います

If I am going to buy at all, I buy fresh, good ingredients.

私はどうせなら新鮮で良い材料を買います

If I am going to buy at all, I buy fresh, good ingredients at the market.

私は市場でどうせなら新鮮で良い材料を買います

If I am going to buy at all, I buy fresh, good ingredients at the market at the weekend.

私は週末に市場でどうせなら新鮮で良い材料を買います