visitor posting expenses

Hi,

I am running a blog from more then 8 months now and I got a request for guest posting.
I am new into it so they are asking me how much should I charge per article.

"Just want to confirm how much is your pricing per article with a ******** link written by us? Also, in case our client wants to add a second link to the same article, is there an extra charge for that? "

I do not actually know how much should I charge.

NIche: technology, latest gadgets and trends
Unique visitor per day: ~700

As I do not have much visitor, so really confused into the pricing section as I know if they have Rich content article that might help my blog as well.

Please suggest what should I do

It depends upon your traffic region and the tool you use for Checking your traffic.

USA and UK traffic is the most expensive traffic. And SEMrush Traffic count is the tool to check the traffic.

And you didnt mention your blogs other matrix like DA/PA, DR and most importantly CF,TF.