I agree with pick about the i-sell-this-domain.com -- I don't see any worth. To put it in perspective, I wouldn't even reg isellthisdomain.com, let alone i-sell-this-domain.com. If you just regged these, I'd contact the registrar to see if they have a grace delete period.
As for BBQParty, I have to disagree with pick to an extent. While it is a decent name, I don't see any reseller paying $xxxx for this. End user, perhaps, but not reseller. Keep in mind that it's .net, and not .com.
I'd suggest trying to contact some potential end users. The first thought that comes to mind is that a BBQ catering company would be an ideal end user. Or maybe a company that sells actual BBQ's. There isn't a lot of exact monthly searches done on BBQ Party (about 2400), but you should be able to find an end user that will pay $xxxx. I wouldn't offer it up to resellers, as I think the most you would get from a reseller is a couple of hundred, if that.