How are the SpareRoom listings ordered?

In broad terms the ads are ranked in this order:

1. Exact location matches
2. Ads with photo/video
3. New Today/Boosted ads
4. Bold ads, verified users, user activity/responsiveness
5. Ad renewal

The sort order is also 'nested', for example:

Brand new bold ads appear above brand new free ads

More relevant brand new ads (in terms of location) appear above less relevant brand new ads

To stop anyone unfairly dominating the search results in a specific location, every two ads posted, renewed or boosted by a single advertiser in any given location will be followed by one from another advertiser.

What do you mean by "most relevant location-wise"?

This will only be applicable in certain searches. If a postcode is searched on for instance, it has no effect. Also, with a wider search such as "London" it has no effect. But with a search on say "West Didsbury", it will return all ads in that postcode (M20), but ordering those marked as specifically being in "West Didsbury" first, above those in say "East Didsbury".