[JohnM 855 T5R]

With your battery charged up, if you can lay your hands on a multimeter (a cheap one is only £10 or so), do the following:

Make sure everything in the car is switched off, doors closed etc.

Disconnect the positive lead from the battery. Select an amp range on the meter, attach one multimeter probe to the positive battery terminal, the other to the cars positive battery lead (I use a couple of large clips I have for the purpose).. You are now reading what current the car is drawing "at rest". It should be somewhere between 25 and 40 milliamps.

With what you are describing, it would suggest you have a drain of 2 or 3 amps or more going on.

Now, one at a time, pull your fuses until you find the offending circuit. Now you can start to investigate each item on that circuit.

Usual culprits are often things like door marker lamps staying on when the doors are shut, glove box lamps remaining on, boot lamps remaining on , all of which aren't visible. Interior lamps staying on is another but you should be able to see that. However, your current drain sounds like it is something heavier duty than that.

Regards
John