Yes, you need to be self-sufficient. To be on the save side, you should have 500 pounds available per person per month. You can make a case with less, if it is sufficient to support you and you have enough income to be not eligible for benefits.

Your husband can also come, but if you apply from outside the EU, he will be judged against the UK immigration rules. If you apply from within the EU (even if you only have a visit visa), you can take advantage of the EU right of free movement. In both cases the visa should be free.

If you want to settle in Germany, the EU has nothing to do with it, and you have to apply for a national visa. You could even apply for benefits, but you may not get a settlement visa for your husband then.