For the past few months, I have been negotiating with my sister who is selling my parents' property and wants me to buy it. I asked for a total amount she would want for the property with some maintenance to be carried out in that price. I used this amount as the basis of our negotiations, and after not being able to lower the price I offered her exactly what she had asked for. She has now declined our offer and upped the price. Is this legal under Property Law? All negotiations were via text message (no real estate involved or solicitors at this stage), however I still have all of our communications.