Louise and I have used white cargo vans from the beginning. If you tape aluminum foil inside every window so that no sun gets in, the interior of the van probably will be comfy 24 hours a day. Probably. That's been our experience, but of course on the playa no one knows.
If you like your parents, I would not borrow their SUV. They will have playa powder blowing out the vents for years to come when they turn on the heater or air conditioner.
My suggestion is to buy a small 3 or 4 person tent as a back up. If you seal your windows with foil, it will be pitch black in the van and you should be able to sleep any time of the day or night - but have the tent as a back up. Our queen size air mattress is a squeeze in the van across the width, but it fits with room to spare on the length. You need to have room on the floor for the mattress and for getting in and out of the van.
You need a shade, again in my humble opinion. You don't want to leave the van doors open - it lets in dust and heat. We've used home made shades and once a ParaWing from some company. You can make a shade from a tarp, bungee cords, and EMT tubing which will fit easily in your van (make sure the longest tube length is shorter than the van floor, though).
See here for some parts to make your EMT shade:
http://www.angelfire.com/biz/shadecanop ... tings.html
there are a ton of sources that will sell you everything but the EMT tubing - go to a local big box hardware and buy it cut to fit your design. Buying the tubes yourself saves on shipping. I recommend side flaps for at least two sides of your shade - if you enclose your shade, you end up in an oven.
Louise and I set up our shade, drive a rebar into the ground beside each leg, and duct tape the leg to the rebar. No guy wires.
Parawings are light and reasonably easy to set up if you've done it for practice a couple of times. Search for them and see who sells them and what price. They don't provide enough shade for my tastes, but that's a personal thing. Because you'll be there for a shorter time, it may be the best thing for you to try as beginners.
See our list of things to bring:
http://www.cieux.com/bm/things.html
which includes links to lists from other people.
Louise has links to places to buy supplies in Reno:
http://civilizedexplorer.pbworks.com/CivExReno
She has a table of contents for the shopping page set up by stores, types of supplies, freeway exits, and casinos.
I recommend that you use everything you're bringing during the next weeks so that you are reasonably comfortable using things before you get to Burning Man. It can get harsh on the playa, and you don't want to try to learn how to set stuff up when it's a hundred degrees or the wind is blowing at 30 or 40 MPH with a dust storm.
I understand you can't be there the full time, but I promise you'll be blown away by the event. Be sure to bring bikes (they'll fit in the van) so you can travel at reasonable speeds. Stop by our camp on Friday at 2:00 pm, and we'll give you clothes so you look like Burners for the weekend. (We give away clothes every year.) PM me the middle of August when we'll know where we'll be camped.