Don't compare Spurs and Arsenal in terms of transfers please

But why don't Spurs want to sell Modric to a Prem team?
It's not like the man himself believes Spurs are contenders for the Prem title otherwise he wouldn't want to leave.

If there's a possibility to sell him to non-pl club, that's way more likely that Levy will let him go. Why should he strengthen his rivals?

..I'm not. It's simple whenever a player wants to leave he eventually will leave the club.

No offence bruv, but United are not Spurs' direct rivals.

and they'll never be if they sell them their key players though

this. Berba forced his way out, and actually - noone misses him.

New stadium will be ready within 3-4 years = Spurs will finally get into same financial level as other clubs. Untill this time, smart signigs (like Vertonghen, Ajax' captain and really good centre back comming there for like 12m + 65k weekly wage, and keeping best players - or eventually replacing them smartly - will let spurs "survive" untill new stadium is done.

Can't wait to see their new stadium.

will it carry the current White Hart Lane name?

No idea.