Based on what I am spending for my machine - similar to Eddy's but slightly larger cutting area, I think - that sounds about right. I'm using profile rails and ballscrews, and prices for those are between about £1000 (Chinese) and £1600 (UK source). Steel has cost me around £400 so far, and I'm going to need aluminium, etc, as well. I'm reckoning that I shall have spent around £2500 by the time I've finished; that's not including electronics, motors and spindle which I also have already. My pricing is also based on the principle that someone, somewhere, will always come back and tell me how they paid less for more of anything that I buy... It also seems to be true that you end up spending more on odd bits and pieces (nuts and bolts, epoxy, whatever) than you expect.

It's quite difficult to come to any consensus opinion based on build logs here; while there is an enormous amount of useful, not to say invaluable, information, there are so many different views on what's wanted that it's quite difficult to find a "reference" design that is close to what you have in mind yourself! Good luck with the project, though.