SciFi channel is infamous for their budget. Normally they only allocate 3/4ths the normal amount of money. RDM and Eick has both commented how scifi has been riding them on the budget since captain's hand and the declaining ratings.
Budget is a huge factor when you consider the average BSG episode runs 2-3 million dollars, and ones like pegasus, ressurection 1 & 2 , captain's hand, lay down your burdens 1 & 2, and Exodus can run as high as 3-5 million each because of all the CG shots and location shoots.
Budget was a huge factor in Enterprise (2-4 million per episode) being cancelled and Stargate SG1 (upwards of 3-5 million).
I should also point out the reason why all the corners are cut on paper and displays from BSG is an injoke about SciFi channel's insistance on cutting corners for the budget.
Pegasus's internal sets are also the sets of the Jupiter II from ost in Space