I was wondering if you can use 2 certificates towards one purchase, or is it limited to 1.

No, you can use as many as have -- so long as the purchase price exceeds the RZ amount (i.e. you can't use $10 in RZC on just $7 of merchandise).

Yea, I used like 4 or 5 on one purchase a few months ago.

Thanks

Is this actually the case? I was under the impression that you can use $10 in certs on a $7 total, but you wouldnt get that extra $3 back. you would lose it.

You are correct.

Also, it's the price of the items not including the tax.