If you want to maximize time and cash, you should zero in on the two most important rooms of the house for resale: The Kitchen and Master bath.
Before you start, consider the neighborhood and your target buyer. Don’t over improve! Establish the quality of comparable homes. Then you can decide whether granite and upgrading to stainless steel appliances make sense, for example. Your kitchen may need more of a budget remodel: painting the oak cabinets, replacing /adding hardware, installing a new faucet, upgrading the light fixture, and a new coat of paint. Same goes with the master bath. Maybe you only change faucets, upgrade lighting and mirrors and add fresh new white towels. You would be amazed how much these changes will help the overall look of your home!