Hello @Abby38,
As you say this does sound slightly odd. When I looked at the link you shared, the per night rate is actually a lot higher than the monthly rate, which suggests to me that the hosts has accidentally put a monthly rate on incorrectly or a special offer which isn't as they are expecting. This host has lots of nice reviews, so I think this is just a setting error. I couldn't see any note about cash mentioned in the listing.
It is a good spot and this difference in cost is something that if you are interested in booking, you should inform the hosts as they are most likely unaware or contact our Support Team who can look into this further.
In terms of your post here, out of respect for the host, I have removed the link.
I hope this helps.
Lizzie
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