I"m sorry for your loss. I would highly suggest you seek professional help on all this, because doing things wrong "WILL" affect what your heirs get. There's two professionals I suggest you get with.
First, an attorney that specializes in wills and estates. They will help you set things up to have the lowest tax impact on both you and your heirs. Remember, with the passing of your husband *you* are a heir now. So this stuff matters for you too.
Next, you need to get with a tax professional for reporting all of your transactions (both purchases and sales) correctly. Doing things wrong will be costly to correct later - either on a later year tax return or your estate return after your passing.
Now since you paid cash for everything, that tells me that seeking professional help is not beyond your means. In the end, it will be significantly cheaper than the fines, penalties and back taxes that will be assessed if things are not done correctly. On top of that, if your state also taxes personal income then you can double those potential fines and penalties because your state will assess them too.
