Dell Monitors, identification?

I have 6 Dell Monitors that were abandoned by the previous owner of my property. All have no Power cord or VGA Connector cables. But I tested all 6 and they work.

#1 What Model and Make is this system?

1. Made in China 1999

2. Have extendable necks

3. Color Black of course

4. CN-0SYMTO-7261-9CM-45NL barcode

5. Model Number is in Chinese so I cant read it

6. It has an HDMI, VGA, Power Plug, Monitor type power plug, USB connections, and what looks to be one of those old USB camera type plugs on it.

7. I attached Photos at the Bottom

#2 How do I measure to get the correct size of the monitor?

#3 And Finally Rick from Pawnstars what do you want to do with it?

I'd like to sell them on eBay. So How Much are they worth?

The buyer would need to supply the Power Cord and VGA Cable which shouldn't cost more than $20 together.