We are unveiling an auction site in a few weeks and to better promote our auction we are thinking of offering $50 credit to all new users within a 2 month period. The $50 credit expires after the opening is over. Is this too long for a site opening? and for the word to get around?
It depends how many people you need to have sign up. If you are looking for 10 then 2 months is too long. If you are looking for 100,000 then 2 months is too short. Another option is to give credit to a limited amount of users. For example, first 100 users to sign up get $50 credit. This way you can control how much credit you give away.
This is a good point. If you can afford to give 50$ away for some time and to a lot of visitors then keep it going for a long time. The longer you have it the more people will register.
You can keep it open as long as you can continue to afford it and as long as you get the desired users signing up.