The West End's slogan is Live..Work..Play. It could just as easily be Live..Work..Decorate. The West End has a couple of great places to shop for your home. You'll need that when purchasing a unit at 211 Union Street.
Jennifer at The Weekender House http://www.weekenderhouse.com/ is a great resource for design and furniture. She assisted me in my own home. Being color blind I gave her full reign on decking out my home and I personally loved her selections.
Hart and Home at 909 Islington St in Portsmouth NH is a furniture/decorating shop. It has lots of great options with an affordability element since it's is a consignment shop. They don't seem to have a website, but Facebook followers can find them here.
Want to keep it local but not finding what you need? Check out:
Cabot House: Vaughan Mall, Portsmouth, NH 03801
Abode Home Furnishings at 775 Lafayette Rd #12, Portsmouth, NH 03801
Summer House Furnishings: 25 Sagamore Road (Foyes Corner), Rye, NH 03870