Absolutely not. Besides, if they weren't purebred, you'd be lucky if you could give them away. And if they were purebred, you probably wouldn't find them at a garage sale.
Years ago when I tried my hand at breeding Maltese, I was more interested in finding them loving homes rather than lining my pockets. And just recently when I had my Chorkie bred, I found loving homes for 2 of the puppies, instead of attempting to sell them for the highest amount which I discovered was upward of $1,500.
IMO, garage sales are mainly for selling stuff you don't use any more for pennies on the dollar just so you don't have to haul it back into the house. I would never consider selling/giving away an animal at a garage sale.