Carputer or Double din in dash dvd player

[D_roc]

I can't decide which to do? I want something that will look good on my car and will also increase the value of it? I'm good at fiberglassing so thought of installing a carputer and also have a gps system for the pc liyng around and a p4computer gathering dust but if i do it will it increas or decrease the value of my car, also how can i hook the carputer to the BOSE OEM ampthanksD