No worries no offense taken< I hope you took none from my comment. Its a matter of perspective. One's small collection may be large to another. I would say make sure you diversify and buy smart.
I'll answer soley based on my personal opinon. Since you asked about a "good size investment", I would say 10k. And anything of that stature should be kept off premises. It's an investment and not a play thing you have to touch all the time. If it also has collector value, then I could see wanting to view it's beauty and keep it close by. That however, is a risk and reward type of thing, you will have to feel comfortable with.