When was the last time you read a book review which talked at length (or at all) about the quality of the formatting? In every case a person recommends, or doesn't recommend, a book based on the quality of the writing.
If you are getting your ebook ready for publication on Amazon (which is a great place to start, seeing as they currently control more than 60% of the ebook market), before you even think about shelling out $50, $100 or more to get your ebook formatted, do yourself a favor and don't.
That's right. Don't pay for formatting unless you absolutely, positively need it. If your book is full of photos, drawings, tables or charts, you'll probably need some formatting so go ahead and check around. But if your book is just text; prologue, chapters, words and an author's page, you can format it yourself in about 30 minutes for free.
If your book sells like wildfire and you actually make money from it, then you can think about investing a little more in your next book and letting someone format it for you. But until then, save your money. Self-publishing is a business, and no successful business should start out in the hole. Give yourself a chance to succeed by putting the odds in your favor and using as little resources as possible to get your first ebook listed.
For instance, you can use the online service Fiverr.com to create your ebook cover for just $5 and ask them to send you a jpeg version (for loading to Amazon.) Done.
Then, formatting is as easy as copying your entire document and pasting into a .txt document. That will remove all the superfluous formatting; invisible things you don't need like indents. Once that's done, take the .txt version and paste it back into a Word document, but don't change it. Save that document as is.
Then, go to Amazon, Kindle Direct Publishing, and create an account. Load your jpeg cover. Then load your .doc. Amazon lets you preview your document before you load it, so check it out. Immediately you will understand how different an ebook looks from what you thought it might look like. If your document still needs some slight tweaking, open it, tweak it and reload it. Do this until it looks readable then save it.
That's it. Your book is loaded and ready.
Can you pay to have your book professionally formatted? Yes. Do you need to have your book professionally formatted? Probably not. Try it yourself first. Even if you don't succeed what you learn about ebook publishing will prove invaluable for future editions whether or not you leave the formatting to someone else.