My best money-saving tip may actually prevent you from spending money at all. Figure out what you really like and what fits your house. For instance, our house feels cottage-like. Even though I think granite counter tops and stainless appliances and gorgeous cabinets are, well, gorgeous, it wouldn't fit in our simple house. It would make the rest of our rooms look shabby by comparison.
Look for unexpected sources of inexpensive materials
Two rooms in our house were painted with leftover paint from my sister's house. I
I paid her some money for the paint, but I know it was below market value. I was happy to get the colors I was looking for, and my sister was glad to
Many paint manufacturers are now selling small sample jars. As someone who can't pick colors well, those sample jars have saved me several times. Even when I've picked the wrong hue, I have taken the paint back in and had the color changed slightly (this can be tricky, but I have a favorite paint guy who can usually handle my color-changing quirks).
As I mentioned, I couldn't believe (and still can't) how expensive fabric is. But look beyond fabric stores. For instance, I found two king-sized duvet covers made of cool fabric at a thrift store for $3. While I plan to use one as a duvet cover, the other will eventually be made into curtains. What about bed sheets? Vintage bed sheets may have really fresh prints, despite their age. While I haven't done this, I would consider making pillows out of old clothes, if I found a pattern I liked.
Before we sold our first house, we wanted to put new linoleum in the bathroom. It just so happened that friends of ours had just put new linoleum in their bathroom and wanted to get rid of the extra. We had to make one extra seam, but it looked good.
And our new house had a similar story. Again I didn't want to do anything with one of our bathrooms until I had enough saved to do things exactly as I wanted them. Well, I decided that time was further off than I originally imagined, so we bought some paint (full price this time) and I stopped by our flooring place. "Do you have any remnants that are this big and in this color family?" They did. For $25, we put new flooring in our bathroom. Again, this was a major improvement with a minor effect on our wallet.