I don't know about costs, you should contact your insurance company for that.

I spent 8 days inpatient once. I can't say I got any extra rest but unplugging myself from my day to day seemed to relieve a lot of internal pressure. I was noticeably less messed up after the stay.

I was really bad at the time; I could barely string together a coherent sentence. I was given a "choice": 'go in willingly or we will make you'. Some choice. I went willingly because I had a rational thought from somewhere that it would be easier to get released if I walked in instead of getting "dragged" in. Turned out I was right about that. I discharged myself against medical advice and that would have been difficult if they were able to legally hold me more than 72 hours or whatever it was. My pdoc was ready to call the police to start the involuntary process. I don't know the letter of the law here or where you live, but, in my very limited experience, going voluntary is better.

It is also better for your well-being. The people in the ward that were there involuntarily had worse attitudes because they were forced to be there, didn't think they should be there so were very angry and disruptive.

I can't say what is best for you and your current situation or that your doctor would go the route of an involuntary commitment but I can say that I never want to return but it was helpful and really boring. Doing balsa wood "art" and hiding from group therapy is not as exciting as it sounds.

I don't know if any of that is helpful to you, I hope you make the right choice for you. Getting better, even a little bit, is a good thing and if it takes inpatient to do it that is okay.