I made this step stool in around four days. It took longer because of the five coats of paint. It has two coats of paint and three coats of finish. It should stand up to many years of use. With the storage area empty, the lid dropping closed can be somewhat loud. I added felt bumpers underneath the top step to dampen the sound. It's light enough for my 18-month old to push around.
The jigsaw cuts weren't always perfect. I filled any gaps and countersunk screws with wood filler. I used a mouse sander to smooth everything out after screwing it all together. The longest part was the painting. I painted every surface, hidden or not, to protect the wood and hopefully make it last forever.
I didn't list an estimated cost because I had to purchase several tools, including a jigsaw, sander, and countersink bits. It was probably user error, but the countersink drill bit was a pain to use. The locking nut couldn't be tightened enough to keep the adjustable drill bit in place.