Few important suggestions during TI4:
- Use items from returns to bet on upcomming matches as much as possible
- Try not to return items to your armory immediately after a match ends, especially if you plan to bet them soon
- Your items may stay in our bots inventories up to 2 months so there is no rush to return them
- Betting from returns is not limited in any way
Overall trading seems a lot better than during Steam Summer Sale but today showed that Dota 2 API is very unstable - so be prepared - keep your items in returns.