Best way to use iPad in Germany on Vodafone billpay?

What's the cheapest way to use the iPad 2 wifi 3G whilst in Germany for 3 days?

Currently on billpay for phone, with an add-on for the iPad.

Did call in to local Vodafone store who advised quite simply "leave the iPad at home" or risk a second mortgage!

Is there any way around this?

Turn off Data Roaming and just use it in free wifi hotspots.

There should be lots of these.

Thanks!

That's great. Thought it would be more complicated than that.