I have one domain name which I never used it and it has .com and I later discovered there is another company with similar name but with .net and they are doing good as once they approached me to sell them my .com which I never did as I had plan to start something which didn’t materialize . its been 11 years now I have maintained the name now I have two options.

The IP popularity and domain popularity each play a part in the overall quality evaluation. If you come across an expired domain with a high link popularity (i.e. a large number of backlinks), but then poor values when it comes to IP and domain popularity, you can assume that these links were obtained in an artificial way. Domains like these will have already caught the search engines’ attention. Perhaps this is the reason why the domain was abandoned. Users that want to start a serious online project should steer clear of these domains.

Once you’ve settled on some domain name ideas, you can head over to a bulk domain search tool such as DynaDot’s to mass check all the names against different TLDs. When you’ve found one (or a few) good candidates, you can simply go ahead and register them for approximately $10 each. The next step would then be to market them. Then finally, it’s a waiting game.

While numbers like the ones seen above are impressive, most domains sell for significantly less extravagant prices and are generally in the two or three-digit range. Not long ago, those who were able to secure general terms (like icecream.com or pizza.com) not protected by trademark rights often found themselves sitting on virtual gold mines. The glory days of this boom have long since passed, and those looking for a profit in today’s market need a keen sense for coming trends.

Great article on what to look for when buying expired domains! I’ve looked at the domain and page authority of expired domains but haven’t checked if they are blocked by Google like you’ve listed. I haven’t pulled the trigger yet to purchase one (probably good that I didn’t since I didn’t do all my homework) but this will make it easier to finally go. Thanks for the great info!

As you can see just within expired domains they have over two million deleted .com domains. Now, this is obviously overwhelming if you’re trying to look for domains. So, you should use a few filters to make the search process a lot easier. To do that, click on the search filter button. Down here I like to click on the Only With A DMAS Entry because that just filters out sites that are really spammy. For sites that that have been in DMAS ever, it means that the site had to be of some quality.
Karn Jajoo heads the premium names program for Radix’s domain extensions: .WEBSITE, .PRESS, .HOST, .SPACE, .SITE, .TECH, .ONLINE, .STORE & .FUN. Radix has made more than $1.75 million in premium domains revenue in 2017 thus far, including the biggest nTLD sale of all times — casino.online, and the sale of business.site to Google for it’s free website builder, Google My Business. Karn considers himself a new gTLD evangelist and has had articles published in The Next Web, Website Magazine, & CMO.com.
Also with the domains, a name which can be cheap for one can be worth gold for the other. Permute the letters in your domain name and try contacting and eventually selling out to organizations that run under those names or contain the letters within. Companies would be keenly interested in buying out the domain names that matches the product's name. Hint : Look for companies on LinkedIn

Many top-level domains, or TLDs, out there have the potential of being sold at top dollar rates. Gone are the days when domain names with ‘.COM’, ‘.ORG’ and ‘.NET’ were known as top-level domains. Newer domain names with ‘.US’ and ‘.IO’ are also worth their weight in gold. All you have to do is conduct thorough research in order to find all the good domain names you can park.
Buying a trademarked domain name could get you into a lot of hot water. Best case scenario is for the trademark holder to force you into handing the domain over and call it a day. Worst case scenario is you get into a legal battle and end up spending an arm and a leg. This is why it might be a good idea to use the United States Patent and Trademark Office’s (USPTO) website to check for trademarks if you’re unsure about a domain name.
Some buyers are a tough nut to crack and they may quote a ridiculously low offer. Explain to these buyers and convince them why the domain is worth more than the quote. If the potential buyer doesn’t agree, fret not, just move on to the next one until you find a willing buyer. Once you finalize the deal, then it’s time to find the best payment mode for the transaction.

If you’re serious about domain flipping, one of the best strategies is to buy expiring domains that auctioned on the market such as GoDaddy Auctions. Make sure you pick domain names that have good traffic, backlinks and SEO metrics, or domains with the generic niche. Expiring domains with a potential for profit can be found using BuycomDomain.com, this is a free website/tool that helps you sort through the domains by different metrics (age, traffic, backlinks, domain authority etc).
For the following TLDs you can now find a expired/deleted domain list. .gi, .gl, .gy, .hn, .ht, .ky, .mu, .om, .pf, .qa, .rw, .sb, .sm, .sn, .st, .sx, .tc, .tl, .ug, .uy They also show up in the Deleted Domains (last 7 days) list and in the Domain Name Search, however they are not in the pending delete list! I do not have a working droplist for them yet, so that is why they are not released in the pending delete list yet.
Current Craze: When PokémonGo was HUGE last year, my domain flipping friends (Matt of Handshakin.com is one) were all about buying domains like PokeStopNearMe(.com) and other related domains associated with the PokémonGo craziness. It’s like the day trading of the domain world. You’re buying domains during the hype and hope to sell them for a higher price quickly before the hype fades.
Another point of concern is that many people feel that squatting or registering domains is unethical. This is because many web developers have a hard time finding relevant domain names for their projects since most of them have already been registered. Many corporate giants also frown upon the domain flipping industry because many domain names relevant to them are already registered.
A good majority of web developers view the domain flipping industry with disdain as they face a hard time finding the right domain names for their own development projects. Domain flipping is also looked down upon by corporate and business entities who register multiple domains related to their trademarks or business names. Actually, it is these people who’re the real domain name squatters!
Let’s play this out with a real example. Say you’re familiar with the real estate market in Tempe, Ariz., and you have the opportunity to purchase tempeapartments.com for $200. This might be a good deal. Tempe has a lot of rental property; it’s  a competitive market; and there’s ample turnover in the apartment space because the city is home to a major university. Ask yourself:
Domain investors build a portfolio of valuable domain names, and attempt to sell them at a profit. Both Sedo and Afternic offer domain marketplaces (also known as Domain Listing Services, or DLS) for investors to advertise their domains to potential buyers. Once the seller and buyer agree, the aftermarket platforms then facilitate the purchase and transfer of the domain(s). As an Enom customer, you’re entitled to list your domains for sale on Sedo, Afternic, or both at the same time. Get started
There is a misconception that good ‘.COM’ domain names are hard to find and so they are more expensive to buy. But once again, this statement holds no water. You can easily check out the ‘.COM’ domain names that are on sale at highly affordable prices. However, the only downside to flipping ‘.COM’ domain names is that you will have to discover them at different places like Flippa.com or private seller portfolios.
There are currently two main types of domain speculators: those that buy domains, build sites around them, and then flip the domain and accompanying website, and then there are those that buy and sell domain names without web sites attached. While both can be very lucrative businesses, the second type is much easier for novices to learn, and as such, shall be the topic of discussion for this article. 
A suspiciously high number of backlinks from some related niche websites that aren’t too great in quality. In my opinion, this could be an indicator that the domain name was using a Private Blog Network (PBN) service or their own PBN to boost their authority…this blackhat tactic can work, but it places your domain name at risk and the PBN owner could pull backlinks at any time.
In order to maintain ownership of a domain, you must renew it yearly. If you don’t, it “expires”. An expired domain goes through several stages before being released again for general registration. The process differs slightly from one registrar to another but it’s more or less the same. GoDaddy explains what happens to domains that expire with them here.