Rahu in 4rd House Is it good for Marriage

When you look for marriage some common criteria to be considered is the planetary positioning in 4th house. Though 4th house is not the house of marriage determines more insight on person's character. When it comes to men's horoscope the 4th house determines character of his month, character of his wife, his luxuries, the kind of home he will reside it including apartments, independent home, luxury cars, quality of cars, family deity and much more
Once bad placement like rahu, kethu, saturn , afflicted moon happens in 4th house this is something to be considered while finalizing the horoscope. Generally 11th house , 7th house are the ones an astrologer looks at to decide a marriage match in practice. But it is necessarily important to go beyond that and look at positioning of lord of 3rd house, which planets are posited in 4th house etc as part of analysis.
Particularly when it is women's horoscope rahu in 4th house is to determine her character and not a good planetary placement. If it turns out that this is kumbha the house in which rahu is exalted the generic character of kumbha rasi is to keep the bad effects under control. Such women are fond of quarrel and pick up fight so easily but with exception of kumbha rasi other positions are something to be taken care of.
Kethu determines character in terms of sexual discipline and when placed in 4th house gives ultimate negative effects
As far as saturn goes the problem could be from mother-in-law after marriage

Person with afflicted moon in 4th house will be full of negative thoughts, always confused mind and totally untrustowrthy