As for the first run payment. Depends on the danger. But I also need some more info to price it out: Who's hiring? Who are they riling up/holding off? Do the PCs know they're the decoy or not.
Basically, I'd go with (prices are total, PCs must split between themselves):
Assuming it's one night, with a possibility of violence, but not expected to kill the enemy:
Small time Jonhson (low level Syndicate member, Gang boss, B or C level Corp) riling up lower level others: 500¥
Small time Jonhson (low level Syndicate member, Gang boss, B or C level Corp) riling up equal level others: 750¥
Small time Jonhson (low level Syndicate member, Gang boss, B or C level Corp) riling up higher level others: 1,000¥
Medium time Johnson (established Syndicate member, B or A level Corp) riling up lower level others: 1,000¥
Medium time Johnson (established Syndicate member, B or A level Corp) riling up equal level others: 2,000¥
Medium time Johnson (established Syndicate member, B or A level Corp) riling up higher level others: 3,000¥
High time Johnson (Major Syndicate member, A or AA level Corp) riling up lower level others: 3,000¥
High time Johnson (Major Syndicate member, A or AA level Corp) riling up equal level others: 5,000¥
High time Johnson (Major Syndicate member, A or AA level Corp) riling up higher level others: 8,000¥
Then adjust as needed. If the PCs are in the dark about the other run, then the above works fine. If they know about being the distraction then increase the payment a bit (+10-20%). If they are expected to kill any or all of the enemies, then double it at least.
As for foci...yeah, what Kot said. The only thing that the player should be concerned about is that, unless there's masking involved, the foci, when activated, will stand out in the Astral (as long as my memory serves me right that is, in the astral one can see the power flowing in and out of foci unless they are masked...of course you have to be able to astral perceive...but other mages can notice and spirits might get interested).