What are the precautions i need to take to sell the house?

Me (co-applicant) and my father have jointly purchased a house in 2009. i have a sister who married against our family traditions in 2003. Thereafter she has forced on our family to develop amicable relations, which we reciprocated. My mother expired in 2010, after which i (brother) slowly came to a certain understanding about things happening, and with a retrospective judgement of the things and issues associated with her,and came to certain negative conclusions about her. My father's background is, he has never been financially well-doing, meaning he was in debts to support us as a family. i have not only repayed most of his debts, but also the house loan defaults after my mother's demise. in fact though we purchased the house at my mother's behest, he could never pay/never heeded to pay the house loan installments as a duty. He completely changed his stance and behaved in a manner that can be considered responsible. At a time, when i was trying to get a foot-hold on my career and future, i got entangled in this property. my father's financial position was taken advantage of my sister, by keeping herself in his 'good', by sending paltry sums, and he reposing more confidence in her. since later half of 2013, i have distanced myself from them. the reason being; i deposit loan amount and monthly maintenance amount every month in his account. in one particular month, i also deposited property tax amount, which he did not deposit, which i came to know after checking the status. he gave an evasive answer, and asked me to deposit more money citing health issue. i told i shall deposit any maintenance amount only if he sells the property. from then i have stopped communicating and also depositing any amount. of recent, they have come up with purchase of the house by my sister. this is totally unacceptable. what is my legal position, what are the precautions i need to take to sell the house to any other party. I am 37 years old, and my father 63 years old.