Just purchased a 1991 mini cooper very cheaply from a friend of a friend but
basically bought blind, it looks alright and runs ok but havent got a clue
yet what problems could be lurking, it has no mot or tax so its off the road
now and as I'm in no rush thought it could be a bit of a project.

Bodywork: The sills look pretty badly (on the surface) rusted when the
carpet is lifted on the inside but 'seem' sound from the outside underside.
The door skins are rusted badly on both doors and theres also spot rust
bubbling the paint work in several places round the windscreen on the wing
etc...

Brakes: Feel a bit spongy, they have to be pressed hard to get any decent
response but no squeels or funny noises.

Suspension: seems to be non existant at the front, certainly doesnt move
when pushed down - is that normal?

Exhaust: noisy, havent established whether this is a sport add-on or just
holey.

Engine: seems a bit rough but starts ok (with a battery pack or jump start -
battery is crap if left even just over night) when ignition is turned off
does continue to run a little sometimes and splutter to a halt.

So my question is where do I start? Its under cover but not completely
protected from elements, thought I'd try first to remove rust to stop
further damage any hints in doing this? Can doors be bought easily second
hand (its BRG in colour), saw I can get door skins but then presumably need
to weld and paint. Can the sills be repaired without stripping the car? Any
suggestions where I could get that done in the London area?

I would like to keep the car so want to do stuff right but at the same time
on a tight budget and have limited time to work on it(trying to maintain a
london bus too!).

Any help would be much appreciated.

Cheers, Gwilym.