RE:RE:RE:BetaPro S&P 500 VIX Short-Term Futures™ Bull+ ETF
Morning smartfinish
You're correct if this was only one contract would expect double either way.
What I found useful to help figure this out is the explanation of contango and backwardation.
https://tradinggods.net/what-is-vix/contango-and-backwardation/
The problem with these reverse ETF's is the odds are somewhat stacked against you for buying high/selling low as the normal action.
Knowing this, can still make money but have to be fast on the sell when a gain is there and be careful buying at the right price.
When learning about how these work a couple years ago got my fingers burnt a couple times but now have a strategy that seems to be working. Hold no more than a couple days tops and only buy when VIX is in the 15-16 range and setting stops of 8-10% gains.
Thats my 2 cents - best of luck.