Free domain worry is definitely a worry. Big one. It means they're a business that can't pay a very small sum for a professional web presence. I pay a very small sum for a professional web presence and I'm unemployed at the moment. This does not bode well for them, y'know, paying writers.
You also say they were interested in her. Just to clarify: did she submit, and then they expressed interest in the book? Or did they contact her out of the blue? Because the latter is a big, big red flag. Legit publishing houses don't need more slush.
ETA: vis-a-vis editing, you might read through
these.
Two general guidelines apply as well. First, new+small publishers start up all the time and go bust all the time, catching overeager authors in the process. Give them a couple of years, see if they're still going. Sounds like you've already told your friend this. Second, in the meantime, make a list of all your friend's dream publishers (or agents). Start at the top with the biggest houses. "They're too big for my book!" Nonsense. If the book is good, it's a fit for any publisher. Sure, your friend is likely to get rejected by the some of the big players. Then move down the list to the slightly big players, the mid-size, the small-but-solid, the established small, and so on. There are convincing reasons to trunk a book before sending it to a publisher that can't get behind it. A trend might catch on in the future, making this an easier sell. Publish badly and it might not sell at all, which can have damaging long-term effects. There are loads of reasons to be careful.
Wishing your friend all the best with the book, and you in helping her.
