Despite all the dire warnings if the garage is sound the creeper should do no harm. My (stone) house has another species of the same genus right up the back (4 storeys) and has had for 20 years. However, we have to trim it 2 x per year to keep it out of the windows and gutters. In summer it can come in and hang on to the curtains if you leave the windows open for a day or 2. BTW seed is going to be a slow way of getting vines compared with acquiring a plant.

Agree with FloralUK on both points: I have had this plant on a fence out back for decades. Now my garage is in not-so-great condition, and therefore, the plant does indeed end up in the garage once or twice each summer. But that's not because it's somehow growing through the structure somehow, but because there are actual gaps for it to climb through.

This vine, like many others, is a rampant and easy grower. I should think you'd be able to find it growing somewhere, and with nothing more than a shovel and a hand pruner (to shorten up), dig a clump or two with great ease.

+oM

Just to add.......those "ivy" covered walls you see at Ivy League universities are not ivy at all but essentially the same plant as the Virginia creeper. Just a different species but with the very same growth habit. You can bet that if they were to do any structural damage to those brick and stone structures they would be removed pronto but those vines have remained in place for decades.