Maybe this will become a proper post later.
Just have a look just after we joined the EU:
Our EU debt
“The UK could walk away from the European Union in 2019 without paying a penny, the House of Lords has said, in a report bound to raise tensions with Brussels in the run-up to Brexit talks.”
WTO Article 24
Article 24 says if a free trade area or customs union is created, duties and other trade barriers should be reduced or removed on substantially all sectors of trade in the group. Non-members should not find trade with the group any more restrictive than before the group was set up.
“EU-Canada trade deal is only model that fits Britain’s terms – EU’s Barnier”
VISA non-requirement for EU
Listing the third countries whose nationals must be in possession of visas when crossing the external borders and those whose nationals are exempt from that requirement, as regards the withdrawal of the United Kingdom from the Union
Irish Border and WTO
WTO says its rules would not force EU or UK to erect hard Irish border
Article 70 of the Vienna Convention on the Law of Treaties says that terminating a treaty does not affect obligations incurred under the treaty “unless the treaty otherwise provides or the parties otherwise agree”.
The Treaty of the European Union arguably does provide otherwise in the form of Article 50, which Britain triggered to leave the bloc. Article 50 says nothing about financial obligations and lawyers could argue it trumps the Vienna Convention anyway.