Ok, here's some wisdom I have gathered over the years. I don't class myself as a pro, but I've read a lot. You need to use my info here and what others have given and decide yourself if it's useful.
Use all advice to figure out the market for yourself in your own way! If you don't learn it yourself your own way then you'll be forever asking others "why this" and "what that"
in Flippa, if you check Just Sold domains, you will notice domains with no meaning or rules of valuable sold for few hundreds, or even thousands
I see sometimes sales of .net & .io and others with many thousands if just check DNjournal and Flippa
Now consider carefully how many domains which do not sell. Are sat in auction listings for years upon years, don't sell and are let to expire.
Millions and millions, and their owners are too looking at these 4 and 5 figure sales and sat waiting and hoping their name is next. But it's just not going to happen. The percentage of total domains sold vs how many are available is tiny. And you have to look at that too.
Think of the lottery. People say "but someone has to win it, why not me", because there has to be
tens of millions of people who
lose for the one or few to win. And when you are "investing" good money on assets (domain names) then you don't want to be with the tens of millions with "hope" and high risk like the lottery ticket, you want to be sure you're going to sell names, and for good profit.
To do this, you need names which people want. This is the absolute golden rule - if no-one wants your name then it's
impossible to sell. If very few people want your name, then it's unlikely to sell as you have to get them to your name among millions of others across various marketplaces etc.
Initially you should let experience dictate what you buy. As you are new, you shouldn't spend more than $100 or a bit more until you are sure you know what you buy is going to sell for at least a little more. Because you stand to lose less given you are likely to pick a name even priced at $100 that simply won't sell, or will takes years.
That said, honestly, I don't think you should buy anything for some time as the names you bought are not going to sell, sorry. You'll look back on this as many people do, and think "yeah, why did I buy those names lol".
So, how do you get a general idea of what names are worth? You have to look at many many many sales, from 6 figures down to 2 figures, and gather this info and paint a picture of it all in your mind.
This allows you to weed out and forget those which sold for $30,000 which you cannot understand why (it happens) and the ones which sell for $500 which were surely worth much more.
You can then with the remaining knowledge see a
realistic overall value of the different names - two word, one word, categories, industries, etc.
Essentially, with the odd and obscure sales out of the picture, what remains are real sales and absolutely therefore what the values were. Yes on another day the sale price could have been different, but there's nothing you can do about that, just learn what things actually sell for. NOT what people want them to sell for based on marketplace list prices!
Concentrate on basic names and ones which people in 'general' and business will want to buy, for example: "[KillerKeyword]Online.com", and not low potential like "SallysHairSalon.com".
Not only is the latter so unlikely to sell, Sally won't likely have more than double figures to fork out, and likely won't understand the point or need to do so for her domain name when they're on her cards and 90% of her trade comes from people local passing by etc.
Kate hit the nail on the head - think about who would use the name, so are there many businesses in this category, is it local or global, is the industry the name relates to a profitable one?
Importantly, how many businesses are likely to be fighting over the name?
What could the name be used for?
If at any point with any of the above questions (and more) do you stop and think "urmm" then it's likely the name is not so valuable.
consider what your approach is and pros and cons.
- Buy 3 names at $100 each that seem likely to sell for $300 or a little more on a better or the right marketplace. - Best case you make $500 or more profit selling all 3 - bad case you sell one for $300 and lost and made nothing - worst case but unlikely if chosen wisely, you lose $300
- Buy 30 rubbish names for $10 reg fee that are likely to never sell - Best case you sell 4 or 5 for low to mid $xx and lose $150 - worst and likely case given bad names is you you lose $300
Also, consider the ones in DNJournal carefully. If it sold for 4 or 5 figures, while there are the odd exceptions, they are likely good names and perhaps you just didn't see the reason for their value.
Good luck - read, learn, read some more, and when you realise domaining is a business and a vocation just like selling stocks and shares (yes there is a lot of similarity) then you might just start making money at it