Best Long Term Investment for $1000???

[AGuinness]

Regardless of the price point, if the objective is to flip I would say:
1. get something you'll enjoy having even if it doesn't appreciate in value, at least you'll get some pleasure out of it.
2. be super picky, find the nicest example you can for the budget, because if it's a superb example for the grade, it will be easier to sell down the road.

It can be difficult to know what has room to grow. I've done some of it and had successes, but also ended up selling for what I bought it for. Not too long ago, I would have said the Frank Robinson rookie was a great candidate, but I'm not sure if things have already gone up after his passing. Regardless, Robinson is an all-timer who is surely underrated.