Most independent garages will be happy to grind / hammer back the lipping on the discs - depending on how bad it is, of course. A lot cheaper than replacement, and even if they are too bad and need replacing, an independent will probably be a lot cheaper than a main agent.

As to pads - well, again, an indie will probably be considerably cheaper than a dealer.

Brake fluid : did they do a test on it, or do they just go by time. A lot of places just go "Change it every 2 years", when it actually only needs changing once it's absorbed a certain amount of moisture (the boiling point gets lower as it ages, so you get it changed once that has happened). Again, independent probably a lot cheaper than main dealer.

I have no idea what a TMS bottle even is.

Basically, ask them for a price for the jobs. Then go to an independent, and ask their opinion on whether the jobs need doing, and a price for them to be done.

The brake pads aren't absolutely critical to get them done this instant - but yes, within the next month or 2. The last thing you want is for pads to completely wear out - then you start getting metal-on-metal wear, and the discs would then be knackered in very short order.

If you get the brake fluid done at the same time, then it SHOULD be cheaper than getting it done separately.

As to the bottle of goo/gunk, I've always found that the 'recommended' swap point seems to be far more geared towards making money rather than needing it changing. But really it depends on your attitude to risk and the price to get it changed.

If they'll supply you with a new bottle for £10 or £100 may well have a big bearing on your decision !