There is a certain subset of rowhomes that are called "painted ladies." They're a little bigger than the normal colonial box rowhomes, have actual front porches instead of stoops, usually some ornate molding on the roof, and bay windows on the upper level. The molding is usually painted in different colors, often bright ones. The most celebrated are probably the ones on Calvert, Guilford and Abell between 33rd and 28th or so, but you'll see this style in a lot of neighborhoods around the city.

There is also another particular subset of rowhome, I'm not sure what they are actually called, but a lot of people call them "keelty" after the developer that built a lot of them a century ago. They're kind of a transition to the modern suburban townhouse. They look like the normal colonial box rowhomes, but are wider and will have a porch with a (usually) green awning, but still retain the flat roof of a rowhome. I have only ever seen this style on the north side of the city, but the style bled into some of the first developments in the inner county as well. I've seen them in parts of Catonsville, Pikesville and Parkville that are right up against the city line.