For choosing partner from the matrimonial site first it is important to find out that whether that site is registered or not. How many people are aware of that site? That can be done through by asking people or friends. If there is any perfect match then find out that whether the registration is done by right person or not. It is not fraud. Then look for the place of living, caste and education qualification.
To find out the qualification it is important to check the certificates. Sometimes wrong qualification or job description is given. It is done to attract the looker. For job description find out the place and period of working. It can be done by giving call or visiting the office. If it is nearby then spend some time to find out that whether that person is working or not. If all things match then call the person over phone. Talking to the person also gives the idea. Then by visiting the home of particular person along with elders is must.
The problem comes if the person is NRI. In such cases it is difficult to find out the actual person. For that proper research should be done. If it is inter caste the find out the type of culture and living standard. Friends and relatives can be good option for enquiring. It is also important to check the criminal records and health condition. Otherwise later it can affect adversely. Number of family members and whether the person is staying at own house or rented. If they say that they are going to build then find out the area of plot. Locality in which they are living is good or not.
All these factors determine the marriage or choosing from matrimonial site. But what counts the most is the understanding and respect between the two. If this is good and honest then it can make marriage bliss.