The one benefit perhaps you have as a collector of 80s toys it seems, is that time is actually your best friend.
Things you want to add, and which are not uber rare prototypes and the likes, are bound to be showing up sooner or later and there seems to always be a deal to be struck.
The most recent example? I was allowed by the GF to order my own gift for our anniversary soon. I had been looking around on the internet auction sites and the likes for an Emperor Dark from Starcom, one of the rarest figures to get overhere in Europe.
He was a mail away exclusive in Canada, and back then there was no internet, and those mail offers where usually native residents only. I found them online for between 60 to 100 USD, but it was even rare to have him with cloak AND staff, and you would not only be paying a hefty amount of shipping, but also import taxes, making it really expensive for another time just expensive exclusive.
But now I found one in Spain, and he knocked me (well, technically her) back for 65 euro incl recorded shipping, and he is even on the way as we speak already.
This is going to be such an awesome gift!
And it is also the perfect example that unless you get offered pristine MIB boxes, you actually have time to wait. Most of these toys are 30 years old, and due to shows like the Toy Hunter, the market is having a bit of an uplift at the moment, as people think they have found the newest goldmine.
So if you can bring it up to wait just a few more years, the market is going to be settling down again in all probability and prices will lower again by about a quarter, especially for not so popular ranges like StarCom and even MASK.
GI Joe, Masters of the Universe (with it`s upcoming movie) and Transformers is a whole other matter though and have markets of their own...