Immigrationboards.com

We are Australians looking to live abroad in Europe for some years.

My husband has British Citizenship via his Scottish Father. I have a ROA and I have a Certificate of Entitlement in my Australian Passport.

I understand to gain British Citizenship I am required to reside in UK for 5 years.

If I obtain British Citizenship is it true I can visit (and/or live), buy property and work in any EU country?

Depends upon their local laws doesn't it? EU is just trade union not a 'United states' of Europe so every country still has different laws according to this link and for example you can click here about information to buy property in Spain.