Awesome, because now is your chance! Tonight on Comic Connect's Jon Berk Collection auction, you can bid on Marvel Preview #4 (1st Star-Lord), and Marvel Preview #7 (first Rocket) could be yours as long as you outbid your competition.
MP #4 has yet to break the $500, despite being a 9.6 with white pages. A similar book sold in May of this year for $695, so if you're gunning for this book I would not go over $700. The MP #7, a CGC 8.5 with white pages, is currently at $260. A 9.4 sold for $30 this past March, but overall there are not many copies of this book on GPA. That's not to say it's a rare book, but this is a strong price for an 8.5.
If you're interested in the original GOTG (you know, before Star-Lord), there is a Marvel Super-Heroes #18, which is the introduction of the Guardians. The book is a CGC 7.0 with white pages, and this book has been climbing up in value. This year alone, another 7.0 sold for $350. There are plenty of copies out there, many of which are listed on GPA. The book probably went up slightly due to Yondu's role in the second movie.
If you're bidding on any of these books, good luck and happy bidding!