EVERYONE wants to save money and do things Fast. Well, almost everyone. Right now, it's all about the bargains and the speed in purchasing power. But in most things for your home, and nearly always in Interior Design, going cheap and fast will not get you where you want to be (I have written about this a few times before in one way or another). This time, let's just make it about the cash.
If you want to remodel or redecorate a home or (especially) build a new home (it can certainly be a condo...), having Professional Design help should be a "no brainer" decision. In construction, there are often many ways to get something built or to lay out a new space or specify construction materials. If you want to just figure it out without considering options or contacting an experienced Pro, what you are saving in fees can very well come back to you in other expenses.
Look for an architect with residential experience if this is for your home (as opposed to your office or other commercial space) and let him -- or her-- tell you how to most efficiently use space. If it's an existing space, you might be able to reassign functions and add less that's new. Where a doorway goes, or a window or a closet end up can save you Lots of money either by re-using what you have or not adding as much stuff or new sq. feet. The structural materials specified by your architect or professional contractor can vary enough that you may be able to take those dollars and get a gorgeous countertop with the savings or re-do the inside of a closet.
As a Designer, I promise that there are often options that will make having the proper help SO worthwhile. I am not a fan of "disposable furniture", but I know and support that some inexpensive sources have wonderful things, as do resale shops, flea markets and online sources (Overstock, E-Bay, Craig's List). "Adaptive reuse" is always a great idea and I am a huge fan of refinishing, repainting, reupholstering. Over-furnishing is pretty pointless and I suggest getting the important stuff and then filling in the smaller items that are more personal as you can and choose to. Many (maybe most) Designers will sell you furnishings or hook you up with vendors. How they charge for that service varies greatly (and I've written posts on that before). As for me, I charge for products based on what it costs me. And, as an homage to my dad (architect and urban planner who would have been 103 a month ago today): "You should tell clients that you are really saving them money when they hire you and you buy things for them". That's paraphrased, but correct. Those of us who do this for a living will keep you (hopefully) from making expensive errors and it won't cost you more ANYWAY!