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We present multi-instrument observations of the disc around the Herbig~Aestar, HD~145718, employing geometric and Monte Carlo radiative transfer modelsto explore the disc orientation, the vertical and radial extent of the nearinfrared (NIR) scattering surface, and the properties of the dust in the discsurface and sublimation rim. The disc appears inclined at $67-71^{\circ}$, withposition angle, PA\,$=-1.0-0.6^{\circ}$, consistent with previous estimates.The NIR scattering surface extends out to $\sim75\,$au and we infer an aspectratio, $h_{\rm{scat}}(r)/r\sim0.24$ in $J$-band; $\sim0.22$ in $H$-band. OurGPI images and VLTI+CHARA NIR interferometry suggest that the disc surfacelayers are populated by grains $\gtrsim \lambda/2\pi$ in size, indicating thesegrains are aerodynamically supported against settling and/or the density ofsmaller grains is relatively low. We demonstrate that our geometric analysisprovides a reasonable assessment of the height of the NIR scattering surface atthe outer edge of the disc and, if the inclination can be independentlyconstrained, has the potential to probe the flaring exponent of the scatteringsurface in similarly inclined ($i\gtrsim70^{\circ}$) discs. In re-evaluatingHD~145718's stellar properties, we found that the object's dimming events -previously characterised as UX~Or and dipper variability - are consistent withdust occultation by grains larger, on average, than found in the ISM. Thisocculting dust likely originates close to the inferred dust sublimation radiusat $0.17\,$au.

Scattering and sublimation: a multi-scale view of $\mu$m-sized dust in the inclined disc of HD 145718