How do you build your sets, single or all in?

[tcdyess]

For those of you that have multiple sets you have been or will be collecting, do you find it better to focus on one set unitil you complete it, or do you multitask and try and pick up cards as you see them? My thought is financially and time wise it might be better to focus on one, but I hate to see cards that I will eventually need slip by. I wish I had unlimited resources, but as most, have to keep it relatively under control.

Obviously it is tougher to get the older sets, and most of the time the cost is higher on them anyway.

I know there are a lot of you that have ultra experience with this, so I am looking forward to hearing some opinions.

After finishing the "first five" I finally figured out what my "master plan" would be, one set per decade (Yankees only):

First Five (completed)
T206 NY Americans (finally completed)
1923 W515-2
1933 Goudey
1941 Play Ball
1952 Topps
1968 Topps (year I was born)
1979 Topps (just love the cards)
1980 and beyond (who knows???)

Thanks,

Tim