I think you need to get a heat gun, it measures the exact temperature on the surface of, for example, the basking spot. just putting a 150 W bulb in place may not be the same in every house and enclosure. for example, i use a 100 W bulb and still achieve good basking temps. it depends on room temp, air flow, and how the lamp is placed. just a friendly tip though.
that way youll know your skink wont burn itself.
shes got some good hides, right?
its not dangerous or misinformed to feed that often as the previous owner did, since he/she probably had the skink while it still grew a lot. it just needs to become adult meals now to prevent obesity and leftover food

Theres silver tannies and yellow tannies, that ive seen. Not really "rare", but tannies are less common to keep than some of the other species in your area. Tannies for some reason got labeled as aggressive due to how shy they are when theyre young, and theyre not as cheap for pet stores to import indonesian wild caught skinks. I think there are some other colours on tannies too.
Georg W on here has showed pictures of really pretty silver and yellow tanimbar island skinks, if you wanna see more tanny photos
