The Buyer's Realtor will want do a walk-through inspection just before or on closing day itself, to ensure that everything is all right. Your Selling Realtor should take care of making arrangements for a key and if there are any problems releasing them, he/she should have the lawyers working on it. There are many circumstances that could lead to a holdup in closing; incomplete paperwork, documents not delivered on time or an uncertified cheque for closing costs. If this occurs, hopefully it can be remedied without causing too much inconvenience.
The walk-through is not intended to be as thorough as an inspection. The Buyers have bought the home at this point and they are checking to ensure that it is in the same state as when they previously viewed it.
Please make sure that you observe the "Seller's Golden Rule", in leaving the home as you would like to find it. It is always best if you leave your property clean, with all unattached goods mentioned in the contract present and in good working order, and all unattached chattels not mentioned in the contract removed