Why instead of setting up a limit on budget, set a limit on other things such as:
Ammount of LR/LBS
Ammount of Substrate/LBS
Ammount of Inverts
Ammount of Fish
Ammount of Corals / Category ( SPS, etc.. )
Like others have said, the limit on the price is something that doesn't regulate properly due to a huge variation. If price "needs" to be taken into consideration, then a big enough buffer needs to be established to take into consideration in order for a decent tank to be created in a city where things are expensive.
Why should a contest's motivation/bottleneck be people trying to find the cheapest possible second-hand hardware/livestock VS. being creative with the things that they could possibly achieve when creating a tank in a certain category?
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