There are many ways to save money on remodeling projects these are a few.
I have gotten furniture online and taken the guts out for bath cabinets. This gives you a wide choice of styles and prices.
Furniture modification also works with desks, bookcases and many other pieces.
Be sure to check with a professional before purchasing pieces to be modified. No matter how easy it looks, it can't always be done.
The toughest thing, in many cases, is matching the finish. This can be time consuming on certain finishes thus increasing cost.
There are some good production kitchen cabinets available. They are fairly well made and once installed reasonably durable.
One way to save is to unbox the cabinets for the installers. It takes a day or more to take all the packaging off and disposed of which may be better spent on actual installation.
Another thing to consider is, after the cabinets are in, before you fill them up, have someone put a clear coat over the existing finish. Production cabinets have robotic finishes which can be incredibly thin. Adding a clear coat will keep it from being worn through too quickly.
Doing your own demolition or hiring some help can save money. Extreme care needs to be taken whenever electrical and plumbing are involved.
Be sure you know where the shut off and breaker panel are before you begin. Electricity should be shut off but leave the water on unless water damage is a of major concern. In most cases things will survive getting a little wet as long as they don't stay wet very long. With the water on you will know immediately if there is a leak instead of finding out after the wall has been dry walled..