You can sell your property directly without the help of a broker or an estate agent also.
You can sell the property without an agreement or receiving any token money too.
You can sell the property by executing the registered sale deed after receiving the entire sale consideration amount just before the registration of the sale deed.
you can take the help of a document writer to prepare the sale deed and get it registered before the registrar's office.
If the buyer would like to have a legal opinion of this property from his lawyer then you may have to give him the photo copy of the relevant documents including the encumbrance certificate to the buyer at a cost and make sure that you make an endorsement in all the relevant documents that these are meant only for reference purpose and not for sale or any other transaction and put a date on which you handover the photo copy of the documents to the prospective buyer.
There is no necessity for you to approach a lawyer to get the sale deed executed, you can read the documents yourself, get satisfied before executing the same.