This is definitely not my niche, but my initial thoughts would be something in between low $XXX and high $XXX to the right buyer.
businessfinacing.com.au would be preferential, but financingbusiness.com.au still has a bit of a ring to it.
If you put it up for sale on the NF AMA I'd be surprised if it got more than $500.
Once again, this is really not my niche and I find valuing finance related domains difficult and can really depend on the buyer.