If you want a dedicated Nasdaq Total view feed your looking at around 1k per month. But that's only going to show you an incomplete picture, you will also need CTS/CQS Consolidated Trade(NYSE) + BATS: BYX, BZX, EDGA, EDGX etc. So you're looking at 2k+ per month.
There is all the FINRA ATS/ Non-ATS" dark pool' volume to consider. IMO Equities depth is quite a lot more intuitive than futures( eg the book always stacks near daily high/lows/ whole numbers/ VWAP etc)-The jumping in front of large orders could still be a viable strategy in some cases. Depends who's running the book.