if you want to maximize your return , you'll need to be patient enough to sell or trade them as singles or small lots......i have over 2 million cards here and only about 10% of them are PROPERLY organized so far....they take up close to 75% of my home....i fully understand both the need and desire to move some stuff and i'd really prefer to either sell or trade up (i've helped quite a few people here with trades that saw me sending them up to 600-700 cards in one big trade in exchange for 10-20 better cards i needed.....they take up space and trading that way takes time.....most player collectors already have this type of material (base and low-end inserts and parallels) so they don't need it which often leaves you looking for set builders or people just starting new collections
if you just want to move them more quickly but most likely with a much lower return value , you have several viable options :
player lots
team lots
set starter lots
these lots can be based on any of many factors : quantity of cards ....total BV of the lot....percentage of the set....
with the player lots , one trend you may notice....everyone has lots of the super stars available , but often it's the minor/regional stars that fetch the best returns quite simply because not everyone takes the time to pull those... (some of my all-time best sellers from 1999-2005 were small lots of herman moore in football and larry walker in baseball)
if you just want to move stuff quickly , you're almost limited to one or more bulk lots that tend to move at very low percentages of bv....while the return is usually a VERY LOW percentage of BV , if you find someone with plenty patience and more free time that is willing to parcel the cards out (quantity over quality from their viewpoint , vice versa from your end) , you may be able to work out a deal to pick up a few very nice PC items ....(fwiw , i am one who tends to look for these type of bulk lots)....
