PLEASE check rear subframe mounting points before purchase. Early E46 are known to have a catastrophic failure where the body separates from the floor.
In U.S this issue is covered under a re-call , even here in Canada people are able to get the BMW Canada to fix it free of charge, but I have no idea about England.
Also check the cooling system: expansion tank, water pump, thermostat, ask when those were changed, because at 133k miles those MUST be changed already.
Everything else is butter with cookies.