Hydro, giant scale is a bit on the expensive side too. Looking to maiden this one Saturday.

Back to the topic. A Hostetler 150 is a plans built airplane and is a pretty advanced build. Odds are it has been built well by an old school modeler. Almost certain that it has an older magneto engine in it of around 30cc to 45cc. Will require a carb rebuild. The servos may be fine depending on what is installed, batteries will need to be replaced and depending on the radio if included may need to be replaced as well.

As to a beginner flying it, all things being equal giant scale is easier to fly then say a .40 or .60 size. The issue is that they won’t tolerate any sort of abuse without damage. The OP is going to need a trainer. Looking up and joining a local club is a good suggestion. As far as the actual trainer is concerned I would suggest something that is large enough to use a 20cc gas engine. Reason being is that he can learn about gas engines as he trains then the big Cessna won’t be quite as intimidating.