Today's Buyers

I do not understand today's Buyers. First they want to buy a home then after they have found a home and enter into a Contract of Sale and then have a professional Home Inspection; why are they ready to cancel the sale because the home is not perfect. Sellers are often willing to make repairs and improvements at the Buyer's request once they receive a copy of the Buyer's Home Inspection; but if a Seller is unwilling to make all of the repairs or improvements why does the Buyer no longer want the home? Sometimes you make a right descision and sometimes you make a descision right.