old_contents: alert("Nothing done yet");
  
new_contents: function increase() {
   if(gold > 100*Math.pow(1.1,house-1) {
      gold-=100*Math.pow(1.1,house-1);
      house++;
      document.getElementById("gold").firstChild.innerHTML=gold;
      document.getElementById("house").firstChild.innerHTML=house;
   }
  }
  window.setInterval(function() {
    gold+=0.1*(1+house);
    document.getElementById("gold").firstChild.innerHTML=gold;
  },100);
  
subject: Update base.js