Here is the pertinent part of the sentence:
"Seller and Purchaser each warrants and represents that it has not engaged the services of any agent, finder or broker in connection with the transaction which is the subject of this Agreement...."
While it is true that "each" is always singular, the question is whether the word "each" can render the plural "Seller and Purchaser" singular by its inclusion in the sentence.
I believe the answer is no, based on the fact that if you replace "Seller and Purchaser" with the pronoun "they," the sentence makes no sense:
"They each warrants and represents...."
But you can't simply remove the word "each" because then the sentence would imply that Seller and Purchaser warrant and represent on each other's behalf, which is clearly not the intent of the sentence either. So the answer, in my mind, is to break up the sentence into 2 separate sentences:
"Purchaser warrants and represents....Seller warrants and represents...."
Any other thoughts or suggestions?