Head towards the building opposite the bus shelter. Firstly you have to get past an invisible wall in between the pillar and the wall of the building you have to corner glitch to get past this. It is also possible to wallride then 180 oliie and turn to get in.
Next you have to bounce your way to the roof to do this move slowly into the corner of the wall with the door. Now get in as far as you can into this corner, you want to have a bouncy wall infront of you and behind you so that you bounce between them. Now boneless or ollie between these bouncy areas and you should bounce your way up.
Make sure you are far enough inside the mansion otherwise when you bounce up you will land on the balcony not the roof.
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