Mars in the second house of horoscope is not a rare phenomenon. There are many people born with Mars in the second house of their horoscope and since the second house is related to money, family, food habits and speech apart from other factors, this becomes an interesting combination.
Consider very basic philosophy. Mars is the energy, excitement and enthusiasm to do something. Even if it gets angry, it will not keep it for life. It has 'do or die' attitude. Mars is a warrior. Second house is known to represent family (kutumba), speech (vaani), food habits (bhojan) and money (dhan) apart from other important factors.
When Mars is in the second house of horoscope of an individual, it will impart the energy to the individual for all that the second house represents.
For example if the energy is in the second house, the person would love to debate. It has been experienced that people with Mars in the second house of horoscope often get very angry while debating.
Similarly, when Mars is in the second house of horoscope, it will make a person foodie. Generally, it is not only Mars but malefic aspect on the second house would make an individual an overeater. May be overeater is not an exact word. What I mean to say is, the person wouldn't know what is good or bad for his health. What he/she wants is to taste everything.
While mars in the second house of horoscope would give the person the energy to earn but at the same time it would make a person spendthrift. As soon as he earned he would spend. It is better if such people don't keep much finance with them.
The energy of Mars would be controlled by different factors mentioned below. Mars in an Agni Rashi (Aries, Leo, and Sagittarius) in the second house of horoscope and Mars in a Prithvi Rashi (Taurus, Virgo, and Capricorn) would yield different results. Hence the astrologer, student or the reader should not hurry to make up that Mars is only bad in the second house of horoscope.
Which sign is Mars posited in? For example Mars in Taurus would behave differently than Mars in Mars in Aries. It would exhibit different behaviors in Aries and Scorpio in the second house.
Which house is Mars lord of in that horoscope? For example if it is the fourth house and ninth house lord, it could yield results different than if Mars is eighth and third house lord.
Which planet is it posited with in the second house of horoscope? Mars with Jupiter or Moon in the second house would be different from Mars with Saturn or Rahu in the second house of a birth chart.
Is there a Jupiter aspect, Saturn aspect, Venus aspect or any other planet aspect on Mars in the second house of horoscope?
If any planet has aspect or is in any yoga with Mars, the lordship of those planets should be observed.
Are those planets weak or strong etc.
The number of considerable points could depend on the astrologer but those are more than those mentioned above. The purpose of mentioning these points was to make the reader aware that astrological interpretations are conclusions of various combinations.