These should be more than enough to get your domain in front of tons of potential buyers. If you did a good job picking an awesome domain, you should have no problem (eventually) selling it. You need to be very patient as it could take months or even more to land a decent deal. A lot of domainers sit on domains for years before actually selling them. This is why it’s best not to obsess over a domain and simply move on with buying and listing others (or going back to your day job if this is a side gig) once you've listed the initial one.
Just like a property listing, except much simpler, domain marketplaces are basically massive lists of domain names that are up for sale. The process of using them is simple. Buy a domain and park it, then list your domain on the marketplace for a price you’re willing to let it go for. Once the domain is sold, the marketplace takes a cut and then passes on the remaining funds to you.
Domain name sellers are advised to use Sedo.com to list their domain name. The real advantage with Sedo.com is the mandatory escrow service that comes with every transaction. The site charges the seller a commission of 15% per transaction or USD 50, whichever is higher, for domain names featured on the site. Sellers who do not list with Sedo.com but would like to use their escrow service will have to pay the minimum transaction fee of USD 50, or 3% of the transaction, whichever is higher.
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.