Well not that it matters but I have 25 years of lifting experience and I own my own business, part of which is of course PT/gym.
Tears is right. Technically I'd recommend a tone-level routine for the neuromuscular facilitation bit, but this would soon turn to a hypertrophy program for most clients. The benefit of the tone level intensity is to avoid making clients hate you right out of the gate (DOMS overkill), but also and mainly to teach the lifts correctly. Balance and cardio stuff can be thrown in right away depending on where the client is headed. A good reason to move from toning weak crap to hypertrophy stuff is that even though the neuromuscular facilitation happens for the most part early on, actual tissue activation and the obvious ability to lift a bit heavier are reasons for moving forward ASAP. And progress is always good to see, which is another reason for the shift to hypertrophy.
I don't have a specific time when I introduce real strength training. Sometimes it's never. But if a client isn't stiff, recovering from a surgery, or whatever, and shows even a speck of interest, I'll jump into that when I think they have a base.
The problem with jumping into strength training is that it actually takes longer to see results, untrained clients will easily get stronger with hyper anyway, and a lot of people aren't aiming for or interested in the strength game. The only way to teach strength programs early is to keep is light and hope you have a really patient client, which never happens.
@ Hurley: you can jump into 5xs etc early if you want but be mentally prepared to see results later, and be prepared to spend a lot of time with light weights until you get the right form. Doing hyper (something simple then maybe gvt next) for the first few months is the faster, better results-based approach.