Looking at the advice, if it was me, I would find the cash as it seems an opportunity to 'try out' double bass with minimal risk. It looks like, with care, you can just tune up and try it.
Obviously a setup would be advantageous but beyond that it would be decide whether to stick with and possibly improve it, or to get a better instrument.
My only advice would be that it seems easy to dislodge the soundpost when changing strings.
It's a far better starting point than the one in this thread: