Small changes to website design/finish

Hi,
I would like to add a transparent circular "SOLD OUT" & "SALE" sign to my four products on my homepage.

Here is a link to what i wanted to achieve on a website I've seen;
http://vantage-shopify-theme.myshopify.com

You can see where they added the signs at the bottom of the page on their products!

And here is my website, where i would like the changes to be made;
https://gofybr.myshopify.com

There are other small tasks i would like to add if you would also be interested?

Please let me know how much this would likely cost?

Many Thanks