In general, formatters will accept books in almost any condition after editing. Good proofreaders will either let you know that your book is either inconsistent, or they will tell you what thye’ve fixed. Your formatter though will accept a book with any options you need to send them it in.
If you want the formatting to go faster, make sure your chapter headings are set to one setting, that the subtitle is set to a separate one and that your book itself is set to Normal or Body text. If you do that, it’ll mean that the formatter can do work faster. That said, you do also make sure that you’re letting your formatter know how your file is set, so it’s easier for them to sort out your books.
Some formatters will format only eBook, while others will offer eBook and print. Some will only offer Amazon only, (if you’re using Amazon’s KDP) while others will offer you all formats. Print is often offered as an extra, and some formatters can make sure that your print and eBook match.