Let's say that you're operating at a 50% profit margin, which is very healthy.

You are selling weaned rats for $1.00 each.

This means that you are making $0.50 per rat.

If you are at the flea market for 8 hours in a day then you would have to sell 116 rats just to make minimum wage.

Do you see how the math doesn't really add up too well in favor for doing it?

You would have to sell 160 rats to make $10 per hour.

If you were trying to make $100 per day you would need to sell 200 rats in 8 hours. That is still only about $12 per hour.

If you need the extra cash you are better off getting a part time job.

I have also only calculate the time that you spent trying to sell your rats. If you could the time that it takes to care for them I am sure that you are losing money.

You just can't sell enough at a flea market to make it worth your while. I know, I have explored every angle.