alajaponaise Mar 6, 2011:

Your both suggestions are OK. It'd be either ｢2008年4月にDBO契約の見積依頼書が発行されました。｣ or ｢2008年4月に設計･施工･運用契約の見積依頼書が発行されました。｣

Ayuko D (asker) Mar 6, 2011:

Thank you all for your kind response. I understand the phrase now.

Krzysztof Łesyk Mar 6, 2011:

Yes, 見積依頼 seems fine here, but assuming "DBO contract" is short for "Design, Build & Operate contract", you might want to include 契約 in there: I'd probably say something like "DBO契約の見積依頼" or "設計･施工･運用契約の見積依頼" if I wanted to be extra verbose ;)