Dishwasher stuck on wash cycle

My dishwasher wont advance from the wash cycle to the dry cycle. A repairman said it had a bad heater element and also needed a control board replacement. When I asked what they did to determine that the board needed replacing he said "oh we just know from years of experience it is best to replace it". With the cost of parts and labor I could buy a new one! I am ordering a heating element and going to try and replace it myself. Do you think I should go ahead and order a control board too? Is it hard to replace these parts?