ownership

[TFL]

I was wondering what the usual time people are with an engineering consulting firm before they are offered ownership? i have been with a company for several years and the owner is always teasing me with being a partner and i was wondering how long people usually wait to get offered a partnership. i guess the question could be asked in two parts- how many years in the industry and how much time with the company.

also how much do people usually pay to buy into a company?

thanks in advance