My SO and I did this on a smaller scale and it was a lot of work! We sanded it down by hand with a fine grain and man, I had no idea how much work and elbow grease it would take.
Luckily, everything went well and we were your DIY amateurs. We had to put on two stains and another one wouldn't have hurt although I was afraid it was going to turn gummy.
Anyhow, hope this helped a little bit. I just followed my SOs lead and worked really hard.