Hi there, I am wanting the player of my game to be able to buy and place buildings anywhere they want (A bit like clash of clans or age of empires). I would really appreciate it if you could give me some advice on a good way to go about this and if so how you might go about implementing this.
Thanks in advance 
This question is way too broad to be properly answered here, but this might interest you:
For the buying part, please write a separate question
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