Testing the water

[gninnam]

Looking to sell my D3 A8 as a project as it ain't well and got to ****ed off with it

As you know, was off work for 7 weeks due to a ruptured tendon and couldn't drive. Left the car for about 4 weeks and then wouldn't start.
Charged the battery and OK.
Didn't try it for around 4 days and guess what, battery dead again.
So bought a new battery. Connected up and car started OK.

Again, didn't use it for a good few days and flat again

Well, since then a few things have now failed.
Keyless entry and start
Climate control (no blower)
Light for the air ride comes on after 10 minutes or so
When cold, squelching noise from the front (suspect top control arms)

Other than that a nice car.

Today, after not using for 2 days, wouldn't start - battery showing 11.5V which should be enough but ODBII showing 10.4...........
Removed battery to put the other fully charged battery in and noticed water underneath
Bailed it out but wondering if this could be the cause of some issues (anyone know what the 2 modules are under the battery?).

So what's it worth as it is (most of you know the spec - I think)