then I'd build in all areas.  If you have enough money, expand enough; if not, expand some, and raise the prices a little.
don' t overdo luxury boxes though, if you build 3 extra you should go a while longer. So also do not raise their ticketprices (yet) until you see if they get filled again or not.
Since it is end of the month I recommend raising the 3 lowest priced seats as follows:  increase lowest with 6%, second lowest priced with 4 or 5 %  and the second highest ticket prices with 2 or max 3%.  Leave the boxes, try to build 3 boxes now.
After building has been done, expand the other seats.  I think a 100/40/15 ratio is fine, but that's up to you, and you should see how your stadion evoluates and adapt to that.
                                
                                
                                
                                
                                
                                
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