I had a lovely stay with my family at Sukhumvit 20.
Sukhumvit 20 guest house is owned by a very nice Indian family. They are so hospitable and sweet. They run a small Thai restaurant just down the accomodation. It was so convenient to grab anything you want from 7 Eleven that is located just opposite the guest house.
Walking to the metro station from the property, you can find many restaurants, street food stalls and other miscellaneous shops.
There is one lovely gift shop on the way to the train station. All you need for the Thailand's gifts is there with so affordable price. I would definitely recommend this property for your trip to Bangkok.