There is an approved list of various criteria, and they must always be studied when looking for a bookmaker: 

1. whether the license is issued and of course the reputation of the bookmaker; 
2. The choice of bets; 
3. whether there are a lot of interesting markets for the event; 
The limitation of bets, and besides the winning (the total amount of sports bets, the maximum amount of winnings); 
5. Money criteria (especially the speed of withdrawal); 
6. Tournaments and bonuses; 
7. The work of technical support. 

This is not a detailed list, but only the main criteria. During the search for a bookmaker, always pay attention to such moments, because they just have an impact on the comfort of using the resource. 

So, we will analyze such criteria in more detail. 

Bookmaker history, and the presence of a state license

At the moment, the license is in fact a strictly mandatory nuance. First - an official license indicates that there is a separate body, which will be an unbiased arbiter in resolving your disputes with the bookmaker's office. So, the legal offices use certified software, which ensures the honesty in their work, as well as the protection of the data and of course the gamer's money. 
And what about history, it will be better to cooperate with a bookmaker's office when there is a certain history, because it allows you to read reviews of bettors and understand the key advantages and of course disadvantages, in case they exist. 

Variety of matches.

First, it is desirable to have a large number of different sports events, so that all bettors were comfortable. Also take a look at whether different leagues and tournaments are organized. This is where experienced bettors tend to make good money. It will be better if there is a LIVE mode, so that it is possible to make sports bets during the match. 

Choice of marketplaces

Every professional bettor tries to find an office that offers a big catalog of different marquets. The key marquees are of course who will win, the number of goals of the team and the penalty kicks. Nevertheless, some love to make more "complicated" bets on other events. So for example quite popular is the event: how many corners will be, or how to score a new goal. As a rule, these markets, offices are ready to give significant odds. If you are a professional in any sport, then it is just this kind of markets to choose it. 

Betting and winning limits

Many today's players simply relax by betting. They come to the office in order to get adrenaline and have no special illusions. In most cases, these gamers perform express bets, because the odds are solid. Of course, in fact, they always lose, but you can get a lot of drive. That is why the minimum level of bets will be an important criterion for such gamers. If the office provides only large bets, then of course it makes no sense to have fun there, because it is a waste. If the bet is small, then the big damage to your wallet will not have to wait. 

Financial nuances

It is important here that the bookmaker's office offers a variety of deposit options, such as Betano in Romania. Also, be sure to evaluate the methods of withdrawal. In addition, it is important to evaluate the speed of sending funds to the account, the speed of payments, as well as the withdrawal limit per month, which exists in almost every bookmaker's office. 

Bonuses and promotions

Bookmaker offices use a fairly effective method that allows you to give a large deposit bonus, and at the same time to earn themselves. This is achieved quite easily. Each player is offered a profitable bonus, though there is a nuance - the wager. If a player agrees, he will have to play it back, and in a limited time. In most cases, beginners can immediately forget about it, because it is very difficult to wagering. So take a look at the bonus wager offered by the office, maybe it is better to refuse such a "generous" gift. 

Technical Support

If a bettor has any questions, it is extremely important to get a quick and detailed answer. Competent technical support is an important factor in choosing a bookmaker's office. 

Conclusion

Basically, we have described the key criteria. However, each participant will be able to find out for himself what will be more important for him. Some people do not care about the range of sports betting, they only want quick withdrawals and big bonuses, others want to see quality support and a wide variety of different betting markets.