Not all shop owners will advise you well on the best board for you - some will tell you the best is the one they can't get rid of.
You will save a bundle buying a second hand board. Just search this forum for discussion on boards and buy what majority claims is very good. Have not tried many boards but Shinn Monk is a legendary favourite of many. I ride Shinn Dundee 135 at 105 kg - it is also a good all around board. At your weight you probably only need a 132-133 long Shinn.
There are other good boards but you can't go wrong with these two if want a general all around freeride board

if your goal is wake-style kiting on flat water, you woul be better off with a stiffer board but it will not ride well in choppy water and you will feel long sessions in your sore joints ( unless you are a young puppy and nothing ever hurts yet



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