Charleston doesn't require a high budget to be worth the trip. The city's main draws (the French Quarter's antebellum architecture, the Battery seawall promenade, Rainbow Row, the City Market, and the waterfront parks) all cost nothing to access on foot. What costs money in Charleston is accommodation and dining, both of which have a wide range. The gap between a resort-priced hotel room and a hostel bunk or budget motel 10 minutes from downtown is significant. The food gap is similar: restaurants on King Street at dinner service price for their location; the farmers market, the grocery delis, and the lunch service of the same restaurants price differently.
The French Quarter: The Core of the Walk
The French Quarter bounded by Broad Street, Meeting Street, East Bay Street, and the waterfront is the area most visitors come for, and it's entirely navigable on foot in a morning. The architecture here, 18th and 19th century buildings many unchanged in exterior appearance, is the draw, and the cost of experiencing it is zero.
St. Philip's Church (completed in 1838 in its current form) and St. Michael's Church (1761, one of the oldest buildings in South Carolina) are open to visitors during daylight hours. Both have churchyards with significant historical graves accessible from the street. The Nathaniel Russell House (51 Meeting Street) is a Federal-style historic house museum with an interior worth the $12 admission if historic interiors are your interest; if not, the exterior is equally impressive from the street.
The Battery, at the southern tip of the peninsula, is a seawall promenade with views of the harbor, Fort Sumter in the distance, and the antebellum homes along Murray Boulevard. It's free, always open, and walkable in 20 to 30 minutes end to end.
Rainbow Row and the French Quarter Backstreets

Rainbow Row, the stretch of Georgian townhouses painted in pastel colors along East Bay Street, is the most photographed block in Charleston and has no admission charge. The best light for photography is morning, before the tour groups arrive and before the afternoon sun creates harsh shadows on the south-facing facades.
The streets immediately behind Rainbow Row (Tradd Street, Longitude Lane, Chalmers Street) have less foot traffic and equally interesting architecture. Chalmers Street has the Pink House (c. 1712), one of the oldest surviving structures in the city. These streets reward slow walking rather than a timed route.
The Saturday Farmers Market: The Food Budget Move
The Charleston Farmers Market runs in Marion Square from 8 a.m. to 2 p.m. on Saturdays, April through November. It's free to browse and covers regional produce, prepared food vendors, and local goods. The prepared food vendors (tamales, samosas, baked goods, smoked meats) provide genuine meal-quality food at $6 to $12 per person, making the farmers market a better Saturday morning food option than most nearby restaurants at those hours.
Marion Square itself is a public park with room to sit. Arriving at 8 a.m. before the crowd builds gives access to full vendor selection and a less crowded park experience.
Where to Eat Without the King Street Premium

King Street dinner prices are the restaurant benchmark that makes Charleston feel expensive. The lunch service of many of the same establishments is 30 to 40% lower in price for the same food quality. Husk, Slightly North of Broad, and Poogan's Porch all have lunch service priced below their dinner equivalent.
The grocery delis in the downtown area, particularly the Harris Teeter on King Street, have prepared food at grocery pricing. For a casual meal after a morning walking the French Quarter, the deli option is consistent.
Bowens Island Restaurant, about 20 minutes from downtown, serves oysters from its own oyster beds at prices significantly below downtown levels. It's cash only, the setting is industrial, and it has no pretension, which makes it exactly what it is: good oysters in an honest setting.
Accommodation: The Gap Is Large

Downtown Charleston hotel rates during peak season (spring and fall) run $200 to $400 per night for standard rooms. The alternatives:
The Not So Hostel (Charleston's best-reviewed hostel) operates in a historic building near the downtown core with dorm beds in the $40 to $60 range per night and private rooms below $150 (verify current rates on the hostel's booking page).
North Charleston, accessible by car or the CARTA bus system, has chain hotels at standard chain pricing, 15 to 20 minutes from the French Quarter with a car.
The CARTA bus system connects the downtown core to North Charleston and Mount Pleasant and runs on a flat fare of $2. Staying in a more affordable area and using the bus adds travel time but cuts accommodation costs significantly.
Day Trip: Sullivan's Island and Isle of Palms
Sullivan's Island, 20 minutes from downtown Charleston by car, has a free beach and Fort Moultrie, a federal historic site covered by the America the Beautiful pass. The beach faces north into the harbor rather than directly south to the Atlantic, which means calmer water and fewer crowds than the Isle of Palms beaches immediately adjacent.
Isle of Palms County Park charges a day-use parking fee (verify current rate at ccprc.com) but provides direct Atlantic beach access. The beaches here are the same quality as resort beaches north of the island without the resort overhead.
The Best Free Half-Day in Charleston

The optimal free morning: arrive by 8 a.m. (before the commercial walking tour groups deploy), walk the Battery, Rainbow Row, and the French Quarter streets to Waterfront Park, then finish at the City Market. The City Market is free to walk through: it's an open-air market in four market buildings running from Meeting Street to Church Street, operating since the 1790s. Local vendors sell sweetgrass baskets (a Gullah Geechee tradition specific to the Lowcountry), photography, jewelry, and artwork. The sweetgrass baskets start at $30 to $50 for small pieces and increase significantly for larger traditional coil baskets, though no purchase is required to watch the weavers.
Folly Beach: The Budget Beach Option
Folly Beach, 11 miles from downtown Charleston, is the beach accessible without resort-level overhead. The county operates a public parking lot (nominal fee; verify current rate at the Folly Beach parking system) and provides beach access directly from it. The beach itself is a wide, sandy Atlantic-facing beach with consistent wave action. The restaurants on Center Street behind the beach provide post-beach food at prices lower than the downtown tourist corridor.
The Folly Beach Pier charges a fishing fee; walking the pier for views is typically free but verify current status. See also: minimalist Savannah weekend.