If you believe (like i do) that Steem & Steemit will succeed, then 1$ is going to be a fantastic price for a long term investment. Even if the price does dive to 70 cents (which it may), Steemit is heading to the moon eventually (in the next year or two maybe).
I was just thinking about buying some steem today. I haven't yet bc my initial rule when I joined was to "mine it" all "organically" through original content creation and curation.
I'm seriously re-considering that as a absolute rule!
I'd say buy your steem in 3rds. Spend 1/3 of what you're willing to invest now and then 1/3 if the price goes down and then 1/3 if it starts on an up trend again.
Similarity if it hits a point where you want to take some profit. Cash out 1/3 at a time so you don't miss out on any further potential gains.
Anyway, that's just my very viewpoint, do with it what you will ;)