In the house, check tops of doors for plugs or holes drilled vertically down into the tops, often holes were drilled to place coins in there. Also, if the window shades have not been replaced yet, pull then down beyond their normal travel range, many people placed paper money and bonds up next to the wooden roller, then rolled shade up to the normal area, who woulda thunk it? Old linoleum in the kitchen was another great place, raise up the edge near any doorways and have a look see. Pull the wood trim around windows loose, many cache's have been stuffed in the space behind them. What kind of heating did the house have in it's day? Fireplace? Check for loose bricks or stones, Old coal furnace? Most were gravity fed, no blowers...so heat registers were in floors, may have been boarded up with new vents being installed on side walls. Look for any floor boards that are shorter in any areas. Newel posts at the top or bottom of stairways, tops may be loose, Bottom step of stairway, pry the top board off, see what's in there. Use portable black light, scan plaster walls and ceilings, any fluorescence means wall was patched and repainted for some reason, especially if it's near the floor. Behind mop boards at the bottom of the walls, specially if they are 3 inches or taller. If there is an old piano around, look all over in it, look under bottom of keyboard, there are usually 2 or 3 slotted screws holding keyboard to the piano, remove them and take keyboard out, brush the dust away. If there were kids in the family, they loved to push coins between the keys. These are just a few of the places I search when given permission to search an old derelict house............NGE