Vault guy,
1972 is my favorite set from my youth, but it's not an easy one to complete.
The first 5 series will be simple though, so I wouldn't even worry about those, you can get those any time. The prices aren't going up on mid grade 1972's any time soon unless they are the high numbers.
I'd say if you want to do set in series, START with the final series .
It's not as easy to find the high numbers in big lots, but that's obviously preferred. I started a second set, and I filled it in no time with the lower series cards. I am stuck now for the second time chasing those psycho high numbers!
If I do it again (I am prone to silly acts like building multiple sets
), I would only get high numbers and then fill in the set in reverse!
And to reply with an update of my own run 1952 -1980 Topps is down to 25 cards. I exclude the 52 high numbers. I am going to a card show today where I think I can get 5 hits. Whoot!