Why not just use 4 HD100's? That solves all your problems right there.

Also, why not hire videographers with their own gear instead of renting their cameras for them. It may be more cost effective than you think.

Hmm, I tried crunching some numbers and I guess I can see how you can get to $4k if you pad it a bit, but honestly there's a lot of room to go down. If you end up going the SD route you can save a ton of money right there by just renting SD gear. XL2s instead of Z1s knocks your budget down to about $2.5k easily, and you get actual shoulderable cameras as a bonus.

I'm with Scott on seeing if you can find some owner/operators. Rental houses rip you off so badly.

I have one operator with his own DV500 - which we'll use at a stretch. The other two op's we are providing cameras for them.

Ideally, I would like to go all HD100 - but there isn't a decent rental house in my city, so we have to go through Dublin - even then the outfit I'm dealing with are primarily Sony-centric and are trying to outsource the HD100's from the UK.