Talk of Cristiano Ronaldo returning to Manchester United often gets carried away in both the British, Spanish and global press. 

Adored is the best way to describe his time at Man United. He joined in 2004 and he left in 2009, but those five years in the red of United were some of the best for United fans alive.

The Invincibles of Arsenal and the 'Special One' arriving at Chelsea were all quietened by this monstrous beauty of a player, unmatched across world football.

An overly arrogant show pony at times, many hated Ronaldo, but no one did at Manchester United. Combining with Wayne Rooney and  Carlos Tevez he was part of one of the greatest trinity of forwards in football history, even if it is not one you think of immediately with the subject.

The talk will die down soon enough of a Ronaldo return but every summer there seems to have been a possibility, is it worth it for Manchester United though?

Cost

Transfer fee

About to reach the peak of his game, United regretfully sold Ronaldo to his dream club Real Madrid in 2009 for a then-world record fee of £86million. With football transfer fee inflation, that just tips over the 100 million euro mark, making him the most expensive footballer of all time, something he is mightily proud of.

United are set to become the richest club in the world. Profits are exponentially rising each quarter and the introduction of Edward Woodward as Chief Executive Officer has seen he club's global brand take a phenomenal rise from a good position anyway. Cost is not an issue in terms of funding it, with Louis van Gaal reportedly having at least £100 million each summer to rebuild his squad.

However, there is an issue of branding regarding cost. Real Madrid are one of the best negotiators of sales in football. Over the past few summers, they have offloaded players they do not want for a bigger fee than players they do want.

Angel Di Maria joined United for £59.7 million, a staggering amount of money that many would argue is only acceptable for the world's best player. To think what they will be asking for Cristiano Ronaldo, football's biggest superstar, is most likely unbelievable. Initial, metaphorical, negotiations would probably see the La Liga club ask for £100million+ for Ronaldo.

To sell him going into his peak and then buy him back for an extra £14million when he's declining in quality would make United look like fools in the transfer market.

Merchandise

There is no denying that Manchester United are the biggest business in football these days. Everything at the top of the club, in terms of the board, is focused on the money-making aspect. 

Stock market performances mean more than results. Whether that is good or bad (it's bad), is another question. Ronaldo's arrivals would see United have both he and Wayne Rooney, two of football's biggest names and two of football's most widely sold names on shirts.

Non-United fans would follow the club, buy a Ronaldo shirt just for their hero. It could, quite possibly, make up for a staggering fee needed to prise him away from the Santiago Bernabeu.

Performances

There is no doubt in any sane person's mind that Cristiano Ronaldo is one of football's greatest players. He has been talked of as one of the greatest ever, alongside sparring partner Lionel Messi. His addition to a United team lacking a clinical finisher, a powerful dribbler and a world-class player would transform that.

Even if he is at the beginning of decline due to age, Ronaldo would be United's best player and the best player in the Premier League. Perhaps United would be unfortunate and get just three years of Ronaldo at his best, but they'd be three brilliant years. The individual quality of Ronaldo can inspire a team to raise their game, leaving United with a better team as a whole.

Conclusion

The signing of Ronaldo would be a great one. The question really is, how can United buy their former man without looking like fools? How can they convince Real Madrid to sell football's biggest star as they falter in the league and Champions League? How can they convince Ronaldo to leave one of Europe's best teams to join a long-term project at United, with the Portugal man now over 30? 

A key thing would be that Ronaldo's quality would help paper over the cracks as United and Louis van Gaal work on their project to rebuild the club. However, this could be bad. United need to properly rebuild and with Ronaldo in their side they'd be expected to win everything every year straight away which could stall the 'philosophy' of Van Gaal and make it fail overall.

It would be silly to say signing Cristiano Ronaldo would be wrong, but it could be that there are too many issues involved for United to even want to sign Ronaldo, let alone be able to.