XML Output Transformation to match importers schema

Avg Bid (USD)
Project Budget (USD)
$30 - $100

Project Description:
I am trying to work out how to take a xml output and transform it so that it matches the input values of sites feeding on xml-feeds with specific values.

Ie my output has say:

Site1 - wants it to read:

Site2 - wants it to read:

...my output is fixed, so I cant alter it to suit everyone.

Instead, Ive been told I need to: "Now as far as a solution goes, you can create custom php files, one for each portal that does not use a mapper. Wordpress gives you all the functions you need to access property posts and it should be relatively easy for an experienced developer to create these files. Then you’d just have to link these files in each portal’s system and you should be good to work with them."

...but I struggle to google my way to what the php files need to contain and how exactly the mapping/transformation from my output to the needed inputs is done.

Can you help?

I need a fixed xml feed ( http://www.key2rentals.com/wp-admin/admin-ajax.php?action=wpp_export_properties&api=1f4e31c2af65ba67d802d7f8a24dd0c42f8b363c&limit=10&format=xml ) to be mapped and auto updating into property portals ... working like this:

Their validator: http://validator.kyero.com/
Their sample feed: http://advertise.kyero.com/assets/kyero_import_sample.xml

So take one dynamic xml feed, from that make another xml feed that is compatible with the portals xml importer

Can you do it? If so, what would it take?

Skills required:
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