I can say i am a newbie myself but in the last few years i have learned a few tricks that may help newcomers get good deals. These tips are my own opinion and how i collect. Whatever you do with this info is up to you.
I mostly collect on Ebay so here are my tricks. They are nothing special really but just a bit of common sense when using the site. I am probably shooting myself in the foot for doing this as this will surely go against me in some way but what the heck... i am in the sharing of information mood right now so here goes...
In no particular order of importance.
tip #1: be patient, what you have found on ebay and lost to another person will eventually come back and generally at a better price and also in better condition. Kenner made a gazillion copies of the same thing. It will pop back up again if it is a common thing.
Tip#2: if you want a deal look for the odd vendor who is clearing their attics. I find that most of the time you will get an awesome deal from someone who does not sell Star Wars stuff on a regular basis. I have had a lot of good luck in finding very good items at very low prices when i looked at an auction where people just wanted to get rid of stuff from their attic.
tip#3: when you have found someone, put them in your favorite sellers list. They might sell one thing this week and in 2 weeks they might sell another item you may like. Check on these sellers frequently.
tip#4: get connected with toy hunters. A lot of people are actually out toy hunting to resell on ebay. A lot of them will put a ton of items on sale at once and you can benefit form those fire sales. So save those toy hunters in your favorite sellers list and check on them often so that you can see if they have a fire sale going on.
tip#5: When those toy hunters make fire sale they tend to list a lot of the same items at the same time...( example: 5 farmboy luke skywalker at the same time) because of that people tend to bid a low prices because at that time the auction is meeting more than the demand. I.E there is more than one Luke so if people loose one they have another to fall back on. Watch for these as i said people do low bid on these and usually you can get a bargain in those circumstances on common figures.
tip#6: watch for items that ends in the hours where everyone is sleeping. Some people actually post their items at a start time where a lot of people are at bed and this means that the auction usually also ends at those time. Most people wont stay up to watch these and they let them slide. But if you have one desirable item that you like it may benefit you to stay up and try to win the auction. I actually did this once and won a darth Vader case full of figures for practically nothing because i had done that. Nobody bid on it except me. So there is proof that it works.
tip7#: search search search. I spent at least 6 hours a week or more looking for bargain stuff. I identify stuff and i put them in my watch list and when i have a hit that i like i watch it until i can win it if i can afford it. By making up your list you are managing your buy list and run chances to get a good bargain.
tip#8: use buy it now. Buy it now can get you real bargains if you search and use them.
tip#9: search for star wars vintage lots. A lot of people will do attic sales and will try to sell their stuff on ebay thru lots. They include the word lot in their selling title. Do not discount the power of a lot. Sometimes you will find gems in a lot that does not look impressive.
tip#10: Look at all the pictures. It will give you a sense of the quality of the sale and in a lot in may help you identify a particular piece you are looking for.
tip#11: use different search titles. A lot of people don't know the names of the things they sell so they will throw in a generic name for the auction. This will throw off the search engine and hide some possible gem from you. You have to look for odd titles sometimes. I have won a MISB mini rig once and it was not named mini rig at all but identified by the seller by the toy number on the kenner box. So anyone searching for that mini rig by name never got a hit to that auction. So if you look for oddball titles you may end up getting searched that no one else are seeing.
tip#12: search in ebay stores. Its like ebay and ebay stores are not connected. sometimes what i dont find in the regular ebay site will turn up in the ebay stores so try both sites when looking things up, you may get a pleasant surprise and find what you are looking for in the ebay stores section.
tip#13: ask for photos. Not sure ask for more photos to avoid being deceived when you receive your item.
tip#14: talk to your seller and ask questions. If they get back to you, its a good sign that they want to do legit business and it may open doors to a good buy.
tip#15: have fun, and never give up. I have had days where nothing i found please me...last week was one of them. I found nothing that i like then all of a suddenly i found something i liked like crazy...so be patient and keep on trucking on and you will get what you need.
tip#16: identify what you need and make a wish list of all the people who have listed this item for sale. That way you can compare the quality of each item, the price, the total end cost to you and the time to buy or try to win the auction.
tip#17: use the ebay app. it may not be the best app ever but it is an essential tool to communicate with people while you are away from home and assist you in managing your purchases.
tip#18: the power of the case. I cant say it often enough. The single figures you buy probably came from cases that were bought on the cheap at flea markets by toy hunters. Hey, its called capitalism but there is no law that says you cant do the same thing. Search for case lots on ebay to find gems. Mind you 90% of the case are duds. either too expensive or full of crappy beaten up figures but from time to time you may find one single figure that you need in that case that is worth the purchase. If you can get a blue snaggletooth from a case without paying too much then you are golden. Mind you this does not happen often but i did purchase a case (as i said above for 35$ plus 30$ shipping...so overall it cost me 60$ + but i got a case that i needed, i pulled the best figures out of the lot and then resold the rest for 35$.. so i practically paid nothing for my auction and my toys.
tip#19: weapons, the darn weapons...you best bet? again a lot or a case. You would not believe the price that some seller charge for some particular weapon while you could just turn around and purchase a lot and get all the guns that you need. Imagine buying a lot that has several imperial blasters in it versus buying the guns piece by piece. A good imperial blaster can set you back a good 20$ versus buying a lot that has the figure plus some weapons for maybe 60-100$. You keep what you need then resell the rest and if you are smart you will end up having paid nothing for your weapons. Plus the advantage of this is that most of the time these are attic sales and you will know that the weapons are indeed legit and not repros.