I like to have V-Flats on location but I have a small sedan car, also wind can throw them away, and also they are not easy to fold and carry around.
I was thinking: if I go to a fabric store and buy some piece of white fabric, then I can put that in my bag and that will weigh nothing, so I can put it up with two light stands and some clamps and wind won't throw it as easily either.
So, is there any type of fabric that can reflect light the way the white side of a V-Flat does?
The 2 lightstands is not a good option for reflective surface for locations. It is a waste of 1 lightstand anyway. And you have now a big parashute.
Take a look at big foldable reflectors: https://www.google.com.mx/search?q=foldable+big+reflector&source=lnms&tbm=isch&sa=X&ved=0ahUKEwj-9f2xrarKAhXKqR4KHSeyBGgQ_AUIBygB&biw=1177&bih=625 The aditional advantage when using it with a boom arm is that you can control the angle of it. Do not abuse the size, becouse if it is too large it could be dificult to controll. Probably a good combination is one about 30" for portraits and one or two bigger for group shoots.
For backgrounds the 2 lightstands are not sufficient. It is important that the bar attaching them is firm, you also need some sandbags. https://www.google.com.mx/search?q=background+stand
For a fabric for background you need a strechable one so you can get away the wrincles. Search for some that has some lycra on it. A common one is Muslin http://www.bhphotovideo.com/c/buy/muslin-fabric-backgrounds/ci/23716/N/3974362653
Normally the fabric has less reflection becouse is translucid, so some light passes to the other side.
Be carefull on one thing. Sinthetic fabric can have a non white color, normally purple or magenta one, so take some samples and make some sample photos.
