If you have a collection of baseball or basketball cards that you would like to sell, here are some tips on the best ways to go about it:

First, take inventory of your entire card collection. Carefully go through every single card and log details like the player name, year, card brand (Topps, Upper Deck, etc.), condition of the card, and any other relevant details. Taking a thorough inventory is crucial for properly assessing the value of your collection and marketing the cards for sale. You may want to sort cards by sport, year, brand, or condition to better organize your collection.

Once fully inventoried, it’s important to properly assess the value and grade the condition of each card. For cards that could potentially be worth $20 or more, you’ll want to have them officially graded by a reputable third-party company like PSA, BGS, or SGC. Getting cards professionally graded increases their value and makes them easier to sell. For lesser value cards under $20, carefully examine each one and assign your own internal grade based on its state of preservation – Mint, Near Mint, Excellent, Very Good, Good, Poor. Proper grading is needed to set fair asking prices.

Now you’ll need to determine the best outlets for selling your collection. Some top options to consider include online auction sites like eBay, peer-to-peer marketplace apps like OfferUp or Facebook Marketplace, local card shops, attending card shows and conventions, or selling directly to individual collectors. Each option has pros and cons when it comes to things like audience reach, buyer pool, fees, and time commitment.

If using sites like eBay, it’s best to sell higher value graded cards individually through online auctions with detailed photos and descriptions. For common lower value cards, you may want to group similar ones into themed lots to attract buyers and move inventory more quickly. When taking photos of cards for listings, use a neutral backdrop and strong lighting to show off details. Be transparent about grading and condition in descriptions.

Whether selling online or in-person, price your cards competitively based on recent sold prices of comparable cards. Use resources like eBay’s “Sold Listings” feature or price guide website like PSA SMR Price Guide to research fair market values. Be willing to negotiate prices within reason if a potential buyer makes an offer. Shipping cards properly is also important to avoid damage in transit.

Card shows provide direct access to many collectors in one location. Set up an organized trade booth or display case and be prepared with value-priced group lots, singles, and supplies for buyers. Bring a mobile card scanning device if possible to look up prices on potential deals. Networking is also key for building your buyer base at shows.

Selling to local card shops or individual collectors directly often gets you the quickest sale but at a slight discount to the true market value since buyers need profit margins. Consignment deals where the shop only takes a commission if your cards sell is an option rather than a flat buy price offer.

With some marketing efforts on platforms like Facebook groups for your local card collecting community, you may find serious established collectors looking to fill out sets that are willing to pay top dollar. Outreach is needed to find those motivated buyers.

With patience and using multiple sales channels, a well-organized collection can typically find a new home within 6-12 months if priced appropriately. Be sure to calculate estimated sales taxes on transactions and properly report any profits for tax purposes as well. With the right approach, selling your childhood baseball or basketball cards can turn into a rewarding experience both financially and nostalgically. Let me know if you need any other tips!