Buyer would not pay for rural delivery

Anything other than letters need to have RD paid with NZ Post, so no, it won't work. At best if you did that it is likely to sit at the Post Office and they will send you a letter to advise you to pay the correct charge, and at worst, it will simply end up in their lost/unclaimed postage section and eventually get auctioned off/disposed of.

You may want to look at using Pass the Parcel as they only charge $2.50 extra for RD deliveries, although that's going up slightly next month. eg an A4 bag when you use your own bag costs $7.80 same island Rural or $8.10 different island Rural.

Kia Ora Jacinta,

If your Buyer wants to pay only the Post & Track option they need to give you an Urban address to send to or pay the Rural charge - these are the options, as was stipulated on your Listing - negotiation is pre-purchase - Cheers.

Ask then for a Non Rural Address to send it to.  Or I just cancel the Trade.

One advantage as a seller booking online, you cannot book without paying the correct shipping,

Not everyone can get to post shop to just post, and now everything is tracked, you cannot get pass

not paying the rural fee, if you have to pay at the counter,

So it is either pay the correct Rural shipping, or provide a Urban address, if they choose not to do either, just cancel the trade,

Yes, I have had one like that in the past, just presuming you would have a post bag, and make a special trip to post shop costing me money and drop it in the box so they can save money? seriously!,