You’ve exaggerated those costs.
no way a taxi or Uber would be those prices. As I type this Uber fare estimator is £75 LHR-EUS and £ 65 the other way,
Avanti first class is closer to 100 than 150 (and cheaper still if you bought standard premier ( first class seat but no food /drink) at the advance rate.
And no way a MAN-LHR return would be anywhere near a £1,000 even in business.