。
I tried to keep it as cheap as possible.
Literal
As-much-as-possible cheaply get-[tried-ようとした].
安くあげる (安く 'cheaply' + 上げる 'finish / bring to completion') is an idiomatic phrasing for 'to get (something) done cheaply / to keep the cost down.' The adjective stem + く + 上げる pattern is productive for 'finish the job with X-ness': 早く上げる 'get it done quickly,' 安く上げる 'get it done cheaply.' ~ようとする frames the action as an attempted try.