The preliminary contract represents a legal commitment between both parties.The seller commits to sell the property and the buyer commits to buy it. you do not have to certify the preliminary contract in front of the notary in order for it to be valid, although, if you do so, this provides more protection for both parties. The preliminary contract is usually drafted and signed in Bulgarian. In case any of the signing parties does not understand Bulgarian, there should be a licensed interpreter present at the signing, and the contract must be translated.There is no problem if the contract is also signed in English if,for example, both parties are English and understand the language, but if the contract needs to be presented to the court or any other state or local institutions, it should be officially translated into Bulgarian by a licensed translation agency. If your lawyer is signing the preliminary contract on your behalf,you may still ask for a translation so that you understand the terms and conditions.