Open matters and open issues and other...

Hi,
once again I am so confused, I have in my mind many words but I don´t know which is the most appropriate,please advise!

1. When you wish to sum up in one e-mail, all important issues which are not yet solved,can you say:

"open issues" ?

2. When you wish to make the point of the situation and mention all the matters which you will have to take care about, can you say:

"open matters" ?

3. Can you use the sentence: "next steps" when you want to inform someone about the things it is necessary to do do confirm the business?

4. Can a price go down? I mean, "If we remove the table, the price goes down" possible?

Thank you in advance for your help!

Pamela