Looking to buy or borrow an old bike

UPDATE: Problem solved. The Community Centre where I'm cycling to actually allows taking the bikes inside so using my "good" bike is suddenly okay. Thanks.

Hi all,

I'm looking for an unattractive bike for short local commutes, which I could leave chained up on the street for an hour without worrying anything will go missing: like wheels or the bike itself.

Ideal candidate would be a bike kept behind a shed for a few years, with a rusty chain and the generations of spiders calling it home. I don't think club members would have a bike like this, but perhaps someone you know?

I have a tiny budget of up to 50 euros.

Thanks,
Stas.