There has been a lot of feedback on the new Shopify Google channel. It seems to work fine for us if your B2C but there is an issue with B2B.
Google Shopping- Merchant centre- requires prices to include VAT. As a B2B supplier we show ex and Inv vat prices. The Shopify Google feed picks up the ex vat price- and there is no way to over ride this in the Shopify Shopping App. They are not going to change it.
There is a solution- not easy to find- but with the help of an SEO Company based in the UK- Hallam Internet- it can be resolved.
You will need to create a Rule in the Google Merchant centre.
Sign into Google Merchant Centre and go to Products then Feeds and click on your feed name. At the top select Rules. Click on Create Rule and search for Price within the pop-up box and select it. Price not Sale price
On the Edit Rule screen click on Conditions under Edit source. Type Price and then select the value for your Price under the Feed Attributes heading at the bottom.
From the contains drop down select is greater than and then add 0 in the Type .
Click on the Set to box below and select your Feed- with Shopify this is an API.
The next step is add a price modification and so click Add Modification. Select Advanced operators (4th box with dots) and then Calculate. From the Arithmetic operator drop drown choose Multiply By x and enter 1.2 and click on the value in the Applied Value box.
Once you have done this select Save as Draft and then click Test Changes
This takes between 10-20 minutes- when done Test it and you are happy with new Feed-so prices increase by 20% and all good click apply.
Changes take 2 hours plus to take effect in Merchant centre-they state