NOVELTY - The apparatus has a carrier (5) i.e. armored wireline (6), conveyed through a borehole (2) penetrating earth (3). A cantilever is placed at the carrier and moved in fluid upon receiving stimulus force. An actuator is placed at the cantilever, and provides stimulus force at frequency less than lowest resonant frequency of the cantilever, where the frequency is zero Hertz. A sensor i.e. resistance strain gauge, is placed at the cantilever, and senses a strain imposed on the cantilever due to movement of the cantilever in the fluid in order to estimate property.    USE - Apparatus for estimating property of a fluid downhole utilized in geophysical industries for hydrocarbon exploration and production, geothermal energy, and carbon sequestration.    ADVANTAGE - The actuator provides the stimulus force at frequency less than the lowest resonant frequency of the cantilever in order to perform displacement versus time measurements of movement or deflection of the cantilever, thus preventing resonance effects from affecting the measurement, and hence increasing precision, accuracy and a signal-to-noise ratio of the measurements. The apparatus allows pressure within a probe to be reduced to extract the fluid from the formation and to cause the fluid to flow into the device from which the pressure can be provided to an instrument after a seal is formed.    DETAILED DESCRIPTION - The property is selected from a group of density, viscosity and visco-elasticity. The carrier is selected from a group of a wireline, a slickline, a drillstring and coiled tubing. INDEPENDENT CLAIMS are also included for the following:    (1) a method for estimating property of a fluid downhole    (2) non-transitory computer-readable medium comprising a set of instructions to perform a method for estimating property of a fluid downhole.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of a downhole tool placed in a borehole penetrating earth.    Borehole (2)    Earth (3)    Carrier (5)    Armored wireline (6)    Logging tool (10)    Formation fluid extraction device (11)    Probe (12)    Brace (13)