How to avoid being cheated by record company

hello my name is michael welodon and my e-mail is michaelweldon24@yahoo.co.uk.i have recently got into writing lyrics of my own and i hope to improve. This website is excellant. Can I ask a question? Its been one I've thought about for some time and i don t know who to ask.ill be brief as i can.imagine you write some lyrics that you are happy with and you take them to the right person in a record company to see what they are worth.they tell you youre lyrics are okay and decide to buy them off you for a fee which you accept.a few weeks later a song becomes a smash hit on the radio and you know straight away they are your lyrics.the record company make millions and you got a small fee.in other words you got stung.im not saying it would ever happen to me sir,but how do you make sure this wont happen to you?i would want a slice of the cake and not a scone;does that make sense?id be greatful for an answer.thanks for your time and ill continue using your website. michael weldon