I tell people Sam was free, and then needed a $3000 knee surgery. It's true.
A lot of people asking about cost see your little dog and think they want one. If they are genuinely interested and not creepy or rude or clueless, I use it as an educational opportunity to caution them against puppy mills, encourage rescue or suggest how they find a reputable breeder (mom on site, pups stay with mom until 10-12 weeks, NO PET STORES, etc. - you all know the drill.) I give them a quick pro/con on Yorkies and explain how Sam is 6 pounds, let them hold her and see just how tiny 6 pounds is and caution them against the under-5 pound dogs if they have kids or have never had a dog before. I explain how Loki came from a quasi-puppy mill (we think) and even though I paid full price for him, has mega health issues that need expensive meds. Except for her knees, Sam is healthy. So, it's NOT get what you pay for UNLESS you do your homework and you must be prepared for anything!
If they ask if I'm going to breed them because they are oh-so-cute then I give them THAT lecture as well.
I figure they are either actually interested, or they will think twice about asking next time!!