If I may say so
I think the it would be Corona's dogs best interests if you could try and find a local rescue that would take her and spay her before rehoming. I appreciate that you are unable to do this, but "selling" her for $50 entire means she could end up in a puppy farm or with pet owners who plan to breed form her to make a few $$$$'s
A good place to start looking for reputable rescues is local vet surgeries, they should be able to give you numbers to call.
Good luck and don't feel bad that you cannot keep her, you are simply being honest. I hope you will consider rescue for her. I think it would be for the best.
Many people can be VERY convincing when they want a dog...especially perhaps when it is for the wrong reasons. Believe me I learned that when I was involved with local rescue!
Best wishes.
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