So the feature I am looking for is as follows -

1. Users can bet by entering an mount of money or units. The bet is received but has to be verified and approved by Admin or Moderators.
2. Once bet is proved it can be shown on a block to the public asking for a challenger.
3. Another user can pick up the challenge and place the same amount of money or units again this has to be verified and approved by the Admin or Moderators.
4. After the results the Admin or Moderators ends the bet.

Here is another good example.

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you need something like an auction? like ebay.com for example?