SQL запроса:

SELECT   wp67_posts.*
					 FROM wp67_posts  LEFT JOIN wp67_term_relationships ON (wp67_posts.ID = wp67_term_relationships.object_id) INNER JOIN wp67_postmeta ON ( wp67_posts.ID = wp67_postmeta.post_id )
					 WHERE 1=1  AND ( 
  wp67_term_relationships.term_taxonomy_id IN (292)
) AND ( 
  wp67_postmeta.meta_key = 'average_price_week'
) AND wp67_posts.post_type = 'boats' AND ((wp67_posts.post_status = 'publish'))
					 GROUP BY wp67_posts.ID
					 ORDER BY wp67_postmeta.meta_value+0 DESC
					 

Первые 20 постов и meta:

ID: 1205 — title: Odisey — meta: ['4800']
ID: 1204 — title: Mareta — meta: ['4800']
ID: 1201 — title: Flash — meta: ['2760']
ID: 1198 — title: Magic — meta: ['1300']
ID: 1195 — title: Zaurak — meta: ['8790']
ID: 1183 — title: Star — meta: ['5261.6']
ID: 1181 — title: Gazer — meta: ['4380']
ID: 1178 — title: Dino — meta: ['15600']
ID: 1177 — title: NN — meta: ['13131.8']
ID: 1174 — title: Indefatigable Prem — meta: ['7620']
ID: 1168 — title: Eschyle — meta: ['5825.6']
ID: 1164 — title: Roko — meta: ['3379.2']
ID: 1162 — title: Elan — meta: ['6098']
ID: 1159 — title: Tomislav — meta: ['4383']
ID: 1149 — title: White Cloud — meta: ['4940']
ID: 1144 — title: Mamboo — meta: ['1760']
ID: 1137 — title: Hakiri — meta: ['5460']
ID: 1134 — title: Kan — meta: ['2440']
ID: 1131 — title: Jenny — meta: ['2040']
ID: 1129 — title: Ria — meta: ['1680']