Hi there, ks15.

I’ve tried this in my QuickBooks and was able to create a rate that calculates 100% for both invoice and expense transactions. 

Let’s try to check if this has something to do with your browser by redoing the process through a private window. If it works fine, clear your browser’s cache or use a different one. Unusual behaviors can sometimes cause by an overloaded temporary internet files. 

Though, if the same issue continues, I’d recommend reaching out to our support team. They’ll be able to help you investigate this further. Here’s how to reach them:

1. Click Help at the top. 
2. Select Contact us. 
3. Provide a brief explanation about your concern. 
4. Click Let’s talk. 
5. Select either Get a callback or Chat. 

Also, with regards to the multi-VAT feature, I’ll make sure to take note and pass this over to our developers. 

Stay around if you have additional questions.