What is the ruling of Sharia on ironing women's trousers that accentuate the 'awrah, bearing in mind that the questioner is prepared to prevent such clothing from entering his shop?

It is permissible to wash and iron women's trousers for a fee, unless these trousers are worn outside the home without proper covering. In that case, it is not permissible to wash and iron them because it aids in immodest display. However, if they are worn inside the home or under modest clothing, there is no objection.