Dev needed for a renting/buying/selling Plugin

Hi~ I’m working on a real-life server (Minecraft version 1.12.2) and use Spongeforge for it to use mods and plugins. It’s still work in progress. The world has cars, planes, ships and cities with shops and houses/apartments where you can live in. Of Course you need money to buy something and that’s because I need this plugin: for buying, renting and/or selling your house/apartment/plot.

Work Needed
I need a plugin like Areashop or Houses. In combination with worldedit (as a mod), worldedit CUI and grief prevention (sponge) it should be working together. Grief prevention is needed to disable block breaking and to give permission to the player who buys/rent the house to place blocks and edit the room. I want to select with worldedit the area which you can buy or rent (example: an apartment). Then I want to give the area a region number or class number for auto pricing the apartment or I can edit the price afterwards if I want to and to give the apartment a name. To buy or rent the apartment just rightclick a sign with the apartment number, if it’s buyable or rentable and the pricing (for renting: pricing per day/week). After rightclicking a message will pop up if he really wants to buy or rent it. After that the player who buyed it is able to place everything he wants and the sign changes to the players name ( and when he needs to pay the rent to live on in this apartment). To reset the apartment after selling it I would like to have a command to “restore” or just “reset” it to clear all the players changes. Maybe “setrestore apartment1 true” or “setreset apartment1 true” to save it and after selling it it automatically restores the original empty apartment.
Well… That’s what I need.

The price needs to be quoted by the develope. I will send half of it before the start of the project. The other half will be sent after the completion.

I want proof of your skills in developing sponge plugins and how good/flawless they are.
The plugin should be closed source. Everything else we can discuss privately on discord or with private messages.

You can contact me on spongepowered or on discord: Yumi(Moko, Leilani, Kirin)#9088

Thank you~