The question is what kind of a job.?
If you are talking about a blue collar job in the construction industry or are planning to drive cabs, life can be tough. Yes in 99% chances your passport will be held and your legal options limited.
However I will answer considering you are doing applying for a white collar job. Here again the key thing is the organisation you join.
If you join a reputed MNC or big local group you can be rest assured your employee rights will be taken care of. I have been working in Dubai since two years and have switched jobs, have never submitted my passport, have got my dues including gratuity etc without any issue.
However things to be wary of if you’re not joining a reputed company or group:
A) you can be fired anytime
B) there will be a pay differential at grades so you have to negotiate hard
C) I have worked in companies with co-workers from around the world. Haven’t faced any racism from them …however there can be individuals with preference ( and this will true in your own country too)
D) don’t join a company which asks to keep your passport.
E) make sure you read your contract carefully and get your chanaged through.
Don't be scared by the horror stories of others. If something is too good to be true then it isn’t . Try and make sure you join a reputed brand.
Blue collar jobs again are a risky affair. But your perspective too will be different. You will hopefully get a much better life than you will have e back home and be able to save a few extra bucks. But I must warn you that life ain’t easy for those guys.