Can you talk a little about subsidy publishing. Is it a good idea for new authors if it's a reputable publisher. Also, if a publisher asks for $4000, is it too much? Do you suppose all of that money goes toward the publishing of the book?
Are you asking about a true subsidy press (aka VANITY press), which will print anything—regardless of quality—for a fee, does no editing, very little or no marketing, and is basically just a printer or POD company (like Press America, Author House, lulu.com, etc.)? Or an author subsidy/assisted publishing program offered by a legitimate publishing house?
Let’s talk about the true subsidy/vanity press first. I rarely recommend using these types of programs for the reasons stated in their description above. They will “publish” anything that arrives with the appropriate payment. They rarely do any editing. They do no design, or they only do stock design. Most of the time they take the files you send and print them as is, warts and all. For this reason, most distributors and bookstores won’t touch these titles with a 10 foot pole. (Also because it is assumed the reason you had to go vanity is that the quality of your manuscript is seriously lacking.)
But let's say you’ve had your book professionally edited, designed and typeset, and it is now virtually wartless. It’s still not a good idea. Your price per book will be too high to give you the needed profit margin to allow the book to be sold in a traditional bookstore.
The only time this option is a good idea is if your book speaks to a very small niche market, you want to print in quantities of 100 or less at a time, you have direct access to the consumer, and you don’t need to sell through a bookstore—for example, if you’re a public speaker in a tightly focused market, and you sell your books after your speaking engagements.
And is the $4,000 too much? It depends on how many copies you are getting, but probably, yes, it is way too much. If you do decide to go this route, I recommend lulu.com. They are a true POD press and only make money when you buy/sell the book. But read all the fine print very carefully.