I want to write a letter that is compelling. My realtor says he's not allowed to attach letters to offers because he can lose his license.In this article we will discuss the specific items you need to prepare in order to submit an offer on a property here in NYC. In order to make an offer in NYC, you'll need two documents. The first is proof that you can actually purchase the apartment. The property and improvements which the Seller is agreeing to sell and which the Purchaser is agreeing to purchase is known as.