If you want to play solo I would look for the Caverns of Time and Battle of the Aspects raid decks. They are probably the most expensive products for the game averaging around 100 each, however, they are fully automated so you can pilot 2-3 decks against the raid deck which is really nice for solo play.
As far as getting cards, blind lots on ebay are dangerous, often times they are purely c/uc from older sets. Make sure the pictures show a decent amount of rare cards so you have some options and variety for deckbuilding.
Some tutorials are here. You can also join the FB group for this and ask questions / read FAQs there. https://www.wowtcgreborn.com/resources
If you want to play solo I would look for the Caverns of Time and Battle of the Aspects raid decks. They are probably the most expensive products for the game averaging around 100 each, however, they are fully automated so you can pilot 2-3 decks against the raid deck which is really nice for solo play. As far as getting cards, blind lots on ebay are dangerous, often times they are purely c/uc from older sets. Make sure the pictures show a decent amount of rare cards so you have some options and variety for deckbuilding.