As someone who tried to make a commission recently (didn't work as planned) I can say that 1000 for the whole thing would be fairly low, even for a semi-professional.
You should use the [Unpaid] and offer the possibility of a payment instead. Otherwise it's a little misleading in my opinion.
Some people might accept to do it for free.

I'm not saying that your wrong to ask it but most people will not bother the handwork for such a small pay.
The city maps are the worst. A well made city, depending on the style, will takes a lot of time to make.

I have seen people sell their product for five dollars.
It's different. Some works require less work and can be sold to multiple people, like brushes. You can't do that with a world map because they are unique to the world they represent.