Buy the new kitchen appliances to sell the apt?

I have 9.5 year old appliances. The fridge is in the top condition. The gas range (Samsung) and the dishwasher (Bosch) are in a perfect working condition, but especially the dishwasher is showing the signs of time. Dishwasher has these dirty/scratches on the stainless surface that I cannot wash away. The gas range looks decent, but one can see that it was bought a long time ago. My agent says "your appliances are fine", but at the same time, I wasn't able to sell the apartment because people complain that they would have to do the kitchen. Not sure if it's worth buying on sale the new stainless dishwasher (say by Whirlpool, currently on sale for about $500 at Home Depot) and a new Samsung gas range.