Is it allowed to change from tax declaration to titled? Can I buy a right of way at least 4 meters wide ?

I am interested in buying a lot, the person who is selling the lot is the grandson, his grandmother is the owner but since his grandmother died, he is the one who pays the tax declaration ( as he said ) and now when I check the lot, there is no right of way, but he said I can just give money to other neighbors to buy the right of way. And some members of the family are living in Mindanao. (Assuming all is in order ) how much is the charge if I hire a professional one to work everything?