Having bought a basic old LP12 and ended up spending more on it then I originally inteneded (who hasn't),I would advise the following spec:
Steel top plate with corner bolt (swap this for something else and you no longer have an LP12)
Corner braced plinth
Cirkus bearing (make bl**dy sure that this is not pitted, as these are extremely easy to damage)
Linn Black oil
New belt
Any original Linn armboard
Fresh springs/ Gromits
Old (turned to plastic) feet
No baseboard
No lid
a Good Valhalla (There are 'better' PSUs, but the Valhalla just seems to be the most fun)
Thin felt mat (new)
If properly set up with an appropriate arm and cart the above will give you a very engaging presentation - don't try to chase more detail/ 3D/ air, you'll be wasting your time and money.
For the arm maybe find a good condition Akito, perhaps a Mission 774 or an Audiomods 4.
There you go,that's my view. There are many others