Well the short answer is No you don't have to sign it if you don't want to.
When you are buying a Las Vegas foreclosure, (which is a bank owned home), most of the agents who are selling these bank owned foreclosure homes are requiring this be waived as a condition of the sale and because the banks won't fill out the SRPD (Sellers Real Property Disclosure) which is a required form to be filled out by the seller of the home.
NOW there is a new law in place that goes into effect Oct 1, 2011 - the SRPD MAY NO LONGER BE WAIVED
The seller may not request or require the purchaser to waive it, and the purchaser may not waive it.
You can go to the NVAR.org to see the info...http://www.nvar.org/Libraries/Enews_and_Health_Enews_Reposit…
But until then, expect most bank owned foreclosures to be asking for a waiver.
The SRPD will most likely be modified soon to have a specific section for bank owned homes, etc
Regardless, when you are buying a home in the Las Vegas area, remember you really are buying it "as is", so make sure to hire a home inspector to get the home inspected before you finalize the deal.
Do I have to sign a waiver of the SRPD? I'm buying a Las Vegas foreclosure and they want me to sign this waiver.