Valliant ecotec pro 28 installation cost ??

Hello

I need to replace my old boiler (13 yrs old Pott. Puma 80) as only the heating works and the hot water is cold.

Can someone please let me know if the following quote is correct from BG for a Vaillant ecotec pro 28 or am I being overcharged???

Thank you in advance for your kind and considerate help and assistance.

Vaillant ecotec pro 28 boiler £861.91
Horizontal flue terminal £240.55
Internal condensate connection £80.96
(should I be charged for this part??)
Boiler replacement installation £789.56
(same place as old boiler)
Connect boiler electrics & test £162
Install boiler filling loop £23.80
Install copper gas pipe(22mmx3m) £62.54
Minor building work(plaster) £88.68
Disposal of boiler £42
Powerflush £344
Magnabooster 2 spirotec £239

COST approx £2935

less warmfront discount £300
Free 2yr homecare200
(I think I'm being charged for
this somewhere in the quote???).

Overall Cost approx £2635

Many thanks
Regards
TW