There is no charge for leasing a commercial plot in Sin.
There are no taxes or other fees to be paid. You keep what you earn.
Sin's managers (i.e.
AuraWater and
Tritonio) may terminate this agreement at any point in time as long as you've been given a 7 day warning. Failure to move out within 7 days may result in repossessing part of your wares or other blocks as payment for cleaning up the plot.
You are expected to use the plot for commercial purposes. Examples of acceptable use-cases for your plot would be shops, offices to advertise or offer a service that you provide from within Sin.
You may not build using materials that are hard to cleanup (e.g. Obsidian) without explicit permission and you may not build anything that may pose a danger to Sin, its inhabitants or its visitors.
You may not destroy the tunnel system under level 16.
If you are about to build something higher than the highest existing shop, speak with the city managers first.
Your plot is 9×9 but your build area is 7×7 and the extra ring of blocks around it is meant only for overhangs like lights, signs and/or decorations, none of which should block the road around your shop.