We have quite a few plants that Summer outside. They stay out colder then most allow before being brought inside. I treat every single plant with an anti-fungal, 3 in 1 Granular, and sometimes Seven over a two day period before bringing them in. Rare we introduce new plants in the Cold months but if so they get a cleanup and those treatments before going into the plant room.
So far, no bug problems but an occasional fungal problem because I cannot lower the Humidity under 50 percent for the Tortoise. Easily handled though... A big problem this year was an electric heater that cooked the room for a couple of days when I had the flu - what a mess, but oh well.
That room gets scrubbed and treated Spring and Fall too.
With new plants though I use the same "isolation" methods I do all year and I am CERTAIN it is worth it.
Grimmy