Yea simple because you could have made an EFTA agreement, but no.. you choose to pander to the pretence that keeping them foreigners out was part of the original question... then it became not simple.
Simple unless you can't work out what to do about the NI border...not simple. Simple unless you don't know what relationship you are going to have with your biggest market...not simple. Simple unless when you are no longer a part of the largest trade block in the world you can be economically crucified by all the big players...simply shafted... So simple because your job's moving to Holland..Simple because you'll still have to keep EU health standards, safety regulations etc, or you can't sell half your goods, and simple because whist sticking to those, US imports of cheap foodstuff/ goods previously deemed unsafe to sell have flooded your home market and bankrupted the factory or farm you work on. Yea: its all so...simple if you're a disaster socialist /anarchist and don't really give a shit: we have so much "simple" to look forward to.
Its also pointless because the fascists dream of Brexit as an "opportunity" just the same as you... but unlike you they have the support and the money and some brutish plans all sorted whist you... well, you have progressed no further than the nursery room of "simple".