The 18th were an infamous band of vagabonds - their looting exploits after Vittoria had nearly seen them sent home from the Peninsula in disgrace - and I imagine they enjoyed plenty of time in Flanders to accumulate some ill-gotten gains before Waterloo. Many of the figures have therefore been fitted with various sacks, bags, extra pistols, and other paraphernalia. Here we see Serjeant Michael Donnelly, flanking troop commander Captain James Grant, with a nice French saddlebag attachment!
Captain Grant was court martialled a year after Waterloo for using "provoking, obnoxious, and insulting language to a Department of Commissiary General".
At the other end of the line is Lieutenant Charles Hesse, with a pair of pistols held in a holster. Hesse was wounded in the arm at Waterloo. He was later killed in a duel, his adversary being Count Leon, an illegitate son of Napoleon.
Here is the troop with Floyd's troop of the 10th.