Dear friends , please tell me about the restoration. There sketch , oil on paper, which was pasted on cardboard. Between paper and cardboard formed many small bubbles (clearly visible in the photo flash Blix ) , also on the edge of some of the paper are missing ( unfortunately they lost) . Whether it is possible to eliminate the work and the approximate cost ? Size 25 * 35cm . And all it cost to restore the pre-sale or not? I would be grateful for any feedback!