Hello,
The system requirements for each Horizon Client in the respective Admin Guide; System Requirements for Windows Client Systems
Not sure I fully understand what questions you are asking in 2 and 3, if you are asking if running SQL on the client machine will consume resources then yes it would.
With regards to Q4, there are published bandwidth usage for both PCoIP and Blast, for example if you are using the Blast protocol the average usage and recommendation is Network Bandwidth Considerations
I also found a previous thread where this was discussed; Network bandwidth requirements for horizon blast clients
Regards
