Technically, BBQ is slow smoked meat, but a lot of folks call grilled meat BBQ.
In Renton, there are at least three traditional smoked meat places, and at least two others that refer to themselves as BBQ.
In no particular order;
Cedar River Smokehouse: Good without being outstanding, friendly, inexpensive smoked meat. If they only had collard greens I'd be there more often.
Three Sisters: Great brisket and greens, but overpriced, sometimes too slow, and ribs that aren't all that.
Longhorn BBQ: Popular and reasonably priced but pretty mediocre. Good chicken.
Aloha BBQ: Hawaiian BBQ grilled meat. Outstanding, delicious, and cheap. Parking lot can be a nightmare.
Best Beef short ribs on the planet.
L & L BBQ; Also Hawaiian: Part of a growing chain, reasonably priced and pretty good.