I have comprised an architectual sketch which depicts not only the lay of the tavern in the future, but also revealed the one-time costs and monthly pay we have to give up in order to run the tavern.
Summary
450gp: Repair and refurbish costs for entire house
50gp: guild licensing & contracts
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500gp one-time cost
50gp: weekly cost for tavern upkeep/personell/food and drink/etc.
Current Progress
I have already payed the 50gp for the contracts and relations. The only thing left to do is repair the tavern and start our first week off with 50gp for maintenance.