Models and items for sale

I want to sell my models See photos. I would like to sell as a group. Please tell me if my listing is wrong. I appreciate any help.
The models - the Yellow GTX box is in original plastic with $10 sticker. The other GTX was opened, has all parts in plastic + paperwork. $7.50 each.

The Airbrush, never opened. Original price $19.99 - Sell $10.00 with finish set (never used).
All together add $10.00 postage - $35.00
I have a PayPal account. I don't know how to communicate with buyers.
Thank you for any help.

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