A small screen (3-4") should be around 30$. i don't know how "budget" it is for that project, but it really would help save energy. maybe you can also get cheaper ones somewhere (had a look on alibaba). there is even color e-ink on the market. everything except audio levels could be well displayed. another advantage, for assistant or others, would be a stable picture on any view angle.

what about an ink-display? at least power consumption would be very low an it would be readable even in brightest sunlight. on the other side it is not so reactive like an lcd or simulare display type.