opening your own venue?

i'm in a hurry at the moment so i'll expand more on it later, but was wondering if anyone here might have some advice, pros/cons, suggestions for opening a venue. lets say (in worst case) something the size of a dive-bar w/ space for a dj booth, stage and decent sized floor. how about (in best case) a bigger club space w/ small adjoining record shop (for some income during the daytime), and making the whole place a sort of art gallery at the same time? any guesses on initial investment, and maintainence costs? any (serious) input would be greatly appreciated. -j.