I understand how you feel about that.
Many others have felt the same way. And what they have found is that....
In other words, empathise with your prospect (genuinely, not falsely). This builds rapport and creates harmony. If you have truly listened to your prospect's reasons for thinking about going into business, you could add that you feel that they can't afford not to join your business as they have already said that they need more income/want to spend more time with family/are fed up with their job etc etc.
The truth is that if someone really wants to change their life then they will usually be able to find the money to join you. Very few network marketing opportunities are asking high joining fees, and a lot of people spend money every month on Sky tv, take-aways etc that they can cut down on if they really want to.
However, be sensible. If your prospect really can't afford the opportunity, then don't be afraid to suggest that it's probably not the right time for them just now and wish them well.