Getting a CPR

I am planning to move to Sweden, and it seems that as a British citizen (if we don't leave the EU!) with a Scandinavian wife and an already established business, I have nothing to worry about with residency.  But the process for getting a CPR, without which you can barely buy a cup of coffee in Sweden, looks harder: the tax office is vague about the criteria and won't give you sight of the application form until you actually come to the office to fill it in.  Does anyone who's gone through this know:

Do you actually have to have a Swedish home address (difficult when you can't buy or rent without a CPR!) or is it enough to have an accommodation address with a friend?

Can they refuse to give you a CPR on the basis of a criminal record check, and if so, on what grounds?

Is there a bottom income level below which they don't accept that you are able to support yourself?

Hoping people can help!