I've had the 70D - filmed the majority of my webseries www.featherlightandpaperthin.com on it. yeah, there were real moire issues - I always got it worst on men's shirts, but the autofocus meant I could shoot in a way that I couldn't with any other camera, and that more than made up for it for me. Would have kept it and loved the camera but moved to Panasonics for the GH4...
Yeah, a lot of what I would say has been said. I'm not sure the value you would get from renting too much will outweigh time on set learning how to use it. 550D/600D. Or borrow something - anything - from a friend. Camera-wise, don't worry too much. Look on you tube for cine-style stuff on a 600D - more than good enough.
Sound is not the same, though. If you're running a crew new to sound, let me make this one suggestion - IK Multimedia iRig Pro (about 180 euro?) going into an iPad. When used with the IK free app, it means you can record extremely high quality audio (24 bit) and then sync in post (record audio on camera only as a track to use later to manually sync to).
The advantage of this is that you can use crew that aren't used to sound or swinging a boom, because the levels are so easy to understand/see. It really is foolproof. get the mic as close as you can, and adjust the iRig volume so that the waveform doesn't go off the graph. Easy.
I filmed a feature-length project with this approach (and a 600D, as it goes, for a lot of it). If you want to see this, have a look at www.featherlightandpaperthin.com for the trailer - it might show you a rough outline.
Reflectors/lights? Meh. I 'run-and-gunned' my way through the whole thing without very much of either. But the sound is key - but needn't be that expensive...
iRig Pro into an iPad or iPhone. Fantastic 24 bit 48khz sound quality for very little money. We recorded a whole web series like this. Seems to be a very well-kept secret...
Ntg3 is a beautiful sounding shotgun/outdoor mic, but you also need a beautiful interior hypercardioid - AT4053 is nice.
The Zoom H4n is adequate, but plenty of other options are better. I think the tascam DR-680 takes some beating for the money, though I think the irig pro into an ipad is underrated and awesome, though no good if you have more than one source and wish to mix...
If it's filmmaking in general you're aspiring to, then you really need to budget for the sound side as well. If you already have this taken care of, apols.
If you have an iOS device, I wholeheartedly recommend the IK multimedia irig pro, or if budget won't stretch, the irig pre, but bear in mind you will then need to sync the sound. Pluraleyes is the fastest way of doing this. Also budget for a decent mic, but an oktava is a good and cheap option, or the ubiquitous rode Ntg2.
600D is great for the money. 70D is fabulous for the auto-focus and changed the way I worked (that is, touchscreen autofocus on long moving steadycam (or wobblecam) shots...). The sigma 30mm f1.4 is cheap, if heavy, and the canon 50mm f1.8 is a no brainer at the price - it's nearly free.
Sound-wise, without hesitation, I would say the IK Multimedia irig pro got into an iPad or iPhone. Just amazing, and so convenient. Just budget for Pluraleyes too.
Konova sliders are fav, cheap and will be trashed by red dust.