Mods for wands and focus items.

I was wondering what kind of mods and/or inscriptions I can put on wands or focus items. I was looking to specificly modify these two:
http://img212.imageshack.us/img212/2601/gw103rp9.jpg
Can I put for example, a +5^50 energy mod on the wand, along with a 20% long enchantment? Or only one of the two? And on the focus item, can I put any +5^50 energy mod on it? Or only +30 health mod? Or nothing because it has the 20/20?

[wiki]Weapon upgrade[/wiki]
[wiki]Inscription[/wiki]

So basically I can't put any mods on it. But I can put insciptions on them? If I were to put a "Hale and Hearty" on the smiting rod, would it get rid of the 10% skill recharge? Or would it be added?