Surge protection, grounding, and battery question

[swiftbug2]

The picture is my current setup. All breakers, fuses, terminals, controller, and inverter are in one location. No breaker is near the panels.

So about done putting together my small pv setup. Been reading around the forum on spds on dc. I'm still a little confused as to where and how many I need. Figured one at the breaker before my controller. Not sure about if I need one out at my panels with a breaker.
I was looking at the cheaper din rail ones on Amazon since atm I'm unable to afford the $100+ ones. I'm seeing them at 1k vdc, 600vdc, and 500vdc.

Next I'm wondering if I need to connect the negative bar to my ground bar

Last thing is i am using the 3rd option from http://www.smartgauge.co.uk/batt_con.html
For my batteries and I was wondering if it's fine to temporarily connect the cables together using a nut and bolt with some tape around or do I need to use a terminal block?

 

[timselectric]

Figured one at the breaker before my controller.

Yes

Not sure about if I need one out at my panels with a breaker.

Optional
But would only protect the panels.

Next I'm wondering if I need to connect the negative bar to my ground bar

Usually no.
But check the manufacturers instructions.

Last thing is i am using the 3rd option from http://www.smartgauge.co.uk/batt_con.html
For my batteries and I was wondering if it's fine to temporarily connect the cables together using a nut and bolt with some tape around or do I need to use a terminal block?

A bus bar is always recommended. But we do weird things for temporary.
Just make sure that it doesn't end up being permanent. Just because it seems to be fine.