Rafa Benitez: Failing to do your research well in advance can leave clubs at the mercy of agents during the cut-throat January sales

In Spanish, we call it a subasta – an auction – and that's what the month that's just finished can be for the managers. The transfer market is difficult and January is even more difficult. It's been made easier by the team of us who are working closely here at Napoli – the president Aurelio de Laurentiis, the sporting director Riccardo Bigon and me, working, talking, working together in the last days of the market – but it's still a difficult time.

It's an auction because clubs like to find different ways of building up the price for the player of theirs who you are trying to buy. I remember one of my first movements to buy a player in England, when I was talking to the manager of the club who was selling. We were talking about the price of that player, who we were trying to bring to Liverpool, and it was polite and friendly. And then I found that the manager was calling other clubs to tell them about his player and about our interest – just to send up the price. Everyone wants to increase the price and increase the profit. Remember the word – subasta.

One of the important parts for us here at Napoli is finding good value in the market. We are all talking and thinking about Financial Fair Play – planning for the future as well as for now, which is one of the reasons why we have bought a 23-year-old, Faouzi Ghoulam, and a 27-year-old – our new centre-back Henrique, who can also play in midfield.

When you don't have big money, like us, but are still looking for players to get the balance of the squad right, it is also useful to have secrecy. The agents always like to say that "this club is interested, that club is interested", in their player – and when the information is out there in the media that helps the agents too. As managers we like to monitor players and move quickly.

That is how it was when we bought the first of the new three players whom we added in January – Jorginho, a midfielder with real quality. We saw him and got it sorted quickly, after our team of three had agreed on the characteristics of the players we wanted.

The good value was a very important factor for a club like Napoli and I think it is the same reason why we are see quite a lot of loan deals now, with Fulham players like Adel Taarabt and Dimitar Berbatov moving and Lacina Traoré being the latest player to arrive at Everton on loan, from Monaco. I saw figures that showed the number of loan deals in the Premier League were up by January, to make 41 per cent of all new deals, compared with 29 per cent last winter.

In Serie A the rise was also big – 76 per cent of transfers were loans. There are specific reasons for that. Firstly, the acquiring club can get to know the player and see if he will adapt to the style of the team. Secondly, the "releasing" club – if we can call it that – loses the wages. We've seen an economic crisis which affects the ability of clubs to spend, in some of the continental countries. I know there has been talk about austerity economics in England and elsewhere and we can say that loans are an idea for times of austerity.

And while we're trying to do our work in this way, we find that the market can have a negative effect on the squads we are trying to take through the mid-point of the season. Everybody is nervous. The players think maybe a new player will come into their position or maybe an offer will come in for them. It makes people feel insecure and that's why I think the best way to organise the market would be to keep it short and quick: just a time in the summer when players can be moved, which ends on 10 August maybe before the season starts. So you wouldn't have a player who has started the season for you – and knows you – then playing against you.

I saw since I last wrote that there was a lot of surprise about some of the players who left England for continental Europe last week. Taarabt was one of them and also people were not expecting to see Philippe Senderos leave for Valencia, who have always known good talent, and then be in a situation possibly to face Barcelona last weekend.

Don't be so surprised, though. One of the good aspects of being a manager is seeing how a player who does not thrive in someone else's place might do that in your own. People forget that the technical aspect of the player is only one part. Other factors can be the confidence of the manager in that player. Maybe the player has not adapted to the city or the country he is in. Look at two of my own players. Last season, everyone was talking about Pepe Reina, my goalkeeper on loan from Liverpool, and saying "Oh, Pepe is now not so good". Now he has come here and has been maybe the best goalkeeper in Serie A this season. Everyone can see his great level. I say the same about Jose Callejon, who was not playing in the Real Madrid team last season but has been fantastic for us. As a manager, your job is to know the player.

The same knowledge helps when you are in the market. We had some very good buys in January at Liverpool, including Daniel Agger and Javier Mascherano, and the key to buying Mascherano was knowing him. I knew him from when he was at River Plate, in Argentina, and I was trying to buy him for Valencia.

The personal relationship helped when West Ham were selling him in 2007 because I could talk to him in Spanish. I was talking and explaining about Liverpool and our fans. That was important because we bought him, of course, and he became a very important player to the fans of Liverpool. Javier was sure and we were sure about that deal. We talked and we moved with speed.

It was the same with Agger. A lot of people were talking about him and we worked hard to get to know about him and then we were able to do our business. No wasted time means no subasta: that's the lesson of the January transfer market.