Alex Souza bought a certain number of hamsters and half that many pairs of parakeets to sell. He paid $2 each for the hamsters and $1 for each parakeet. On every pet, he placed a retail price that was 10% over what he paid for it. After all but seven of the creatures had been sold, Alex found that he had taken in for them an amount of money exactly equal to what he had originally paid for all of them. His potential profit, therefore, was represented by the combined retail value of the seven remaining animals. What was this value? Again, please explain your answer.