Rashford would be, or should be at least, significantly cheaper than Lookman if it happens this summer. On similar money it would be Lookman all day, as there is more risk with Rashford. Very much doubt we're looking at Rashford for the money United blab about or would dream of. We're looking at him hoping that he'd come in a cheap loan for this season with a buy option to push the expense into next season. IF he delivers.
United would do much worse than loaning Rashford to an offensive powerhouse like Barca. If he doesn't look the money here, he'll not prove it anywhere else. Flick's system is an attacker's wet dream, and Rashford would be surrounded with quality left, right, and center in our offense. Other than PSG, who are stacked, Barca could drive his price the highest for United to sell on a decent deal in 2026.
As nobody is stupid in Europe to pay 40m for Rashford with no guarantees, they could pay 40m next summer for a player that may reinvent himself in a much better team.