Using two adjectives in a sentence

There is certainly no problem in premodifying a noun with two or more adjectives. But you then need to decide:

• In which order should they be?
• Should they be separated by commas?

To answer these questions you need to understand the difference between coordinate and cumulative adjectives:

Coordinate adjectives are those that each separately modify the noun. For example, an old, dilapidated house or a big, heavy box. The house is old and dilapidated, and the box is big and heavy. You need the comma and you can remove either of the adjectives and still have a correct description: The old house, the heavy box.

Cumulative adjectives are those that modify the unit that follows them. For example, a bright red box, which means that the box is red and the red is bright. You cannot remove bright and have a fully correct description: a bright box. Nor can you put and between the adjectives: the bright and red box or switch them around: a red bright box or put a comma between them: a bright, red box.

Whether adjectives are intended to be understood as coordinate or cumulative is not always clear-cut. In your case I regard them as cumulative. It is the 'revised invoice' that is attached. Please find the attached and revised invoice does not sound right. This means that there should be no comma:

• ?Please find the attached, revised invoice.

and that the adjectives cannot be switched:

• ?Please find the revised attached invoice.

You could solve the problem by moving attached one word to the left:

• Please find attached the revised invoice.

Or if this is too formal, then simply:

• The revised invoice is attached.