Apart from pending delete and auction domains, you can use our domains crawler that lets you scrape websites in bulk to find domains that are available to be registered and have amazing backlinks. Your personal crawlers run on our servers and are entirely web based. You do not need to install any software or have a VPS or proxies in order to do use them.
I'm not against making money in any way, but $400 doesn't really seem worth the effort and coffee expense invested (I like the good stuff). This is a very basic example used to put the costs in perspective. Most SEO providers charge more than $50 per hour, and you get what you pay for. The above example of a final labor estimate is probably much higher, or if the domain is already ranking high and the owner wants to sell, so is the initial purchase price. Since this is often repeated many times over for multiple domains, it could get time consuming, and expensive.
There is always a learning curve in buying domains with the purpose of reselling them. Don’t hesitate to ask a lot of questions to those who went before you, participate in forums such as namepros.com and dnforum.com, keep abreast of industry trends via resources like domaining.com, and reach out to the Afternic and GoDaddy Aftermarket support teams.

If you buy keyword specific domains, you're really buying the type in traffic.  I use the URL builder and redirect through that URL so you can see how much traffic your getting from the keyword domain.  There seems to be no rythme or reason to what keyword domains deliver traffic and what don't.  By tracking traffic with the Google URL builder you get a feel for what names are giving you traffic and which are not. ie. the plural, the singular, two words, three words, the possessive, etc.

.ac .ae .ag .ar .at .au .be .bg .br .by .bz .ca .cc .ch .ci .cl .cn .co .cr .cx .cz .de .dk .do .ee .es .fi .fm .fr .gd .gg .gi .gl .gs .gy .hk .hn .hr .ht .hu .id .ie .il .im .in .io .ir .is .it .je .jp .ke .kg .kr .ky .kz .la .lc .li .lt .lu .lv .ly .ma .md .me .mn .mu .mx .nl .ng .no .nu .nz .om .pe .pf .pl .pm .pt .pw .qa .re .ro .rs .ru .rw .sb .sc .se .sg .sh .si .sm .sn .so .st .su .sx .tc .tf .th .tl .tn .to .tr .tv .tw .ua .ug .uk .us .uy .uz .vc .wf .yt .za

Don’t get me wrong, I’m not saying marketing your domain is not important. But, if you’ve bought a bad domain and you do (and overdo) everything laid out in this section and more, it’s still very unlikely that it would sell. It’s like spending car flipping and spending a huge amount of money, time and effort perfecting a car’s paint job, except that this car’s engine is completely fried. You’ll never be able to drive it anyway, no matter how awesome the paint job is, it’s irrelevant.
Your domain name registrar may provide you with a free one-page Website tool, which you can use to create a “this domain is for sale” landing page. Alternatively, you can create a single page (perhaps a hidden page hanging off one of your existing websites) that indicates that your domain names are for sale. You can then forward all of your domain names that are for sale to that one page.

You can’t tell us (with a straight face) that aged dictionary word .net and .org domains won’t sell easily. The .net extension is technically OLDER than .com, and holds an equally intrinsic value to that of its .com counterpart. These LLLL .com’s that are just letters slapped together may be cute to look at and easy to sell, but in the eyes of Google, ANY aged domain that makes sense (i.e. a dictionary word) is going to be much easier to rank for than some acronym or hodgepodge .com…and at the end of the day, that holds more value than whatever society sees in these nonsensical “wqij.com” names.

Link popularity: the link popularity is a parameter that is used to quantitatively evaluate incoming links to a website. This is measured depending on the number of links to a domain according to the mantra 'the more incoming links, the more important the site'. Link popularity is generally determined by the PageRank algorithm. The PageRank only plays a minor role in determining the domain’s relevance.

There are many different ways to buy and sell domain names. Many standard domain registrars, such as GoDaddy.com, will facilitate sales via auction. Meanwhile, specialized websites, such as Sedo, are designed exclusively to buy and sell domain names. Finally, parking domains with a for sale page is a great way to draw targeted interest from potential buyers.
Here's a test I have in process.  I bought an old $5 closeout domain from Godaddy TDname expired auction.  I put a quick minisite up and linked to it with a crazy anchor text phrase.  The domain is ranking for that crazy term now.  It's gone through one pagerank update and I'm waiting for a second to come.  Then I'll redirect the domain to another minisite.  I suspect the second site won't rank for the anhor text, but we'll see.  
A rule of thumb that I follow is when I purchase a domain name I have to believe that I can flip it for a 100% profit.  So if I spend $500 on a domain I need to feel like I can sell it for no less than $1,000.  This way, even if I’m wrong in my estimation I still have some room to still turn a profit.  And if worse case comes to worse case I’ve sold domains before for a $0 profit (it happens even to the best of us).
HIM: "Mainly small-medium sized local businesses looking for a way to increase their ranking. Most already have a branded domain in place, and have heard that using a keyword domain can help. Or they have seen a competitor ranking using that method. The problem I face is that they don't have a lot of money to spend, so I get lowballed on the asking price. There have been a few that make a ton of profit vs what I purchased it for, but that boils down to luck: what is for sale, when I find it, things like that."
In theory, you could technically acquire a domain for $10,000 and be able to sell it for $100,000. You could also acquire a domain for $10 and be able to sell it for $100,000, $10,000… or $100, you get the picture. Because of this, it’s hard to recommend a perfect starting budget because your strategy, experience, and the pace at which you learn will hugely affect your buying and selling decisions.