Billboard or other Vinyl roof cover

[Foxnsox]

Hi all,
I've been making my first yurt. It's a tiny playhouse yurt for an outdoor preschool program I run. After this one is finished, I'd like to build a 20 ft one on my own.

Now for this one, I've got some billboard covers, but as I was fitting one for the roof yesterday, I found it still had a horrendous vinyl offgassing smell, so much so that I developed a headache.

So the first question is, does anyone with experience using billboards know if this smell will go away?

Obviously if it wont, I'll need to get something else.

Which brings me to my next question. I've read about using vinyl coated polyester. I've found what seems to be a very cost effective choice, but am wondering if it's too good to be true. It's around $6.10 a yard if you buy 50 yards. Is this realistic for a decent product?

Thanks for any help
Fox