I would say that I spent $1.50 on 4 lbs of homemade hashbrowns, while I spent $4.00 on 4 lbs the other day.
It really wasn't too hard at all, and took me about an hour and a half total time, but during that same time the kitchen got cleaned, and quite a few other necessities - you'll see why.
First I washed the potatoes. Scrub 'em good!
Then I started a pan of water to boil to blanche them.
Sort according to size. A regular size potato should take about 5 minutes in the water, but the little ones, maybe not as long. I spent a lot of time using a meat thermometer on the potatoes. It should be about 160 degrees in the center.
Now that I know a bit better, I won't always need to use a meat thermometer, but it helped me figure out how soft/firm the potato should be. It can't be fully cooked or you'll have mush, and yet it can't be undercooked or you'll have black hashbrowns.
This by far took the longest time. But I set the timer on my microwave to keep track of how long they were in there. That helped me a lot. During that time I was cleaning up the kitchen, putting stuff away, etc.
When they were cooked through, I put them in a big bowl and then in the fridge overnight.
The next day I grated them with my hand grater, after I peeled them. If you have a food processer, it would take a lot less time.
Have fun trying this!
Update: when I took my hashbrowns out of the freezer, they turned brown. I would make them into cheesy potatoes or some other recipe. If the potatoes have fluid on them, they don't turn brown. One of the recipes I use, uses raw potatoes in a freezer bag and as long as the potatoes are covered with chicken broth, they don't brown at all.