143 is done on sc land but dhakil kharij is not done

a farmer who is sc has done 143 on his land and sold his 2400 sqft area to a person whose category is general.ow we are thinking to buy a part of it i.e 1600 sqft area from 2400 sqft from that person. will mutation of a land can be done and weather its a good decision to buy a sc land as dhakil kharij is not done on that(on person's name from whom we will buy).And how we will know that land is not disputed. P.S We will take home loan to buy this land. religion- muslim