Go for it.
I rebuilt a crashed R1200gs. It was great fun. I got the bike at a good price and worked out a repair budget. The on-road cost came in well below the price for a used equivalent. So I went for it.
The saving is that you are paying for parts only and prepared to overlook cosmetic damage. If the bike is being repaired for insurance there would be the additional cost of labor plus replacement of expensive parts such as engine covers etc.
For me, I got the engine rocker covers welded up and repainted. I purchased brand new forks from BMW. Got the front wheel straitened. (Only a small bend in it) new brake disk. Found a good frame, triple clamps, fairing frame and telelever from various wreckers.replaced all steering,suspension and wheel bearings with new. Glued up the plastic bits myself. Purchased a GS-911 so I could repair and reset the various faults. That was in my budget too, though I kept it for use on my x-challenge and now my F800.
The bike was in good mechanic condition and safe. I did not cut corners on the important bits. Like steering and brakes. I also reviewed my repair plan with the local BMW mechanic in case I had overlooked something important. It used no oil. Ran like a dream.
When I sold it I sold it to someone mechanically minded and gave him full disclosure of the bike. The damage it had, and exactly what I had done to repair it. He got the bike at a good price and was happy.
I owned the bike for 18 months and sold it for what it owed me. Which is good. I was personally not keen to sell to someone who was not aware of the background and did not understand what was done to it. maybe naive of me, but I wanted the buyer to be happy with it.
I got lucky with getting it registered for the road. It is a little more difficult here now and I know some people have been burned by paying too much for the bike and underestimating the cost of repair.
So, I recommend doing it. it is great fun and you get to know the bikes very well. Just do your homework and work out a budget before starting.
Good luck, and keep us posted.