Check out King Charles Cavelier Spaniels. They range between 12 and 20 lbs and would live in an apartment quite happily. They are the friendliest, happiest little dogs and come in 4 different colours, black and tan, tri-colour, ruby and Blenheim (gold and white). Their coats are not difficult to maintain but they sometimes get stuff caught in their long ears. They love to play with balls, squeaky toys and frisbees. Beacause of their size, Cavaliers will fit into a small travel dog carrier and can fly tucked under your seat. My daughter has flown out of province with hers on more than one occassion.