Sid Lowe, the Guardian's Spanish correspondent was making the point that Barca have splashed a fair bit of cash but it hasn't worked out, in your very list you have Mascherano (who has worked), Sanchez and Cesc who have been fairly recent signings.
Oh and AusKnight, you can double the fees for all of your signings.
Mash has been good, when played in the right position. At the moment Barca are stocked in the Cm/DM position pretty well through the A and B team, so he is expendable in the end for a decent fee.
Sanchez has flopped compared to his fee and hype, unfortunately that's not his fault, like Cesc he is often played out of position to accommodate for the big 3. If he was able to free roam around the wings like he did at Udinese, they would probably get his full potential, but highly unlikely considering neither Messi or Iniesta would be played in another spot.
The Chances of Fabregas leaving are very slim, and hes Xavi's Successor, but if he does i can only see him going back to Arsenal, and with Barca needing a CB, a deal for Thomas Vermaelen could be penned out, with Barca also still owing 40% of the Fabregas fee, it could help them if he went. If Not im sure they will push hard for Vincent Kompany or Mats Hummels
Plus They have Thiago and Rafa Alcantara to take his place, you have Sergio Roberto in reserves who is getting close to being just too good to play reserve team football, so he either get promoted or loaned, cant see barcelona selling him anytime soon as hes a born and bred Catalan. Plus i still think Sergi Samper will be better than all 3 in a few years time when he hits 20.
With the Prices, Vorm only has 18months left on his contract, unless he signed a new one so the fee shouldn't be too high
Isco has a buyout clause of 30mill, but malaga need money so i could see them making a deal around the 18-20 mill mark+ throwing a player in if they have too.
Neymar. No one will pay 50mill for him, he will go for around 35- 40 at the very most, he is unproven outside of brazil, so that could and should keep his price down.
The rest its hard to gauge how much they could go for, dortmund could settle for 12mill, or they might want 20 who knows.
Barcelona though do have some really good youngsters coming up, Gerard Deulofeu could very well be the next Messi, he has all the talent in the world, the only thing stopping him at the moment is the fact he plays Messi's position.
Plus Samper is a brilliant up and coming CAM in the Fabregas mould, has great vision, two footed and holds up play well and Dongou could be anything from the next Eto to Heskey, hes a comparable player to Lukaku, just Romelu was more advanced because of being in the Anderlecht first team from 16 years old.
