I hope you don't take offense to what I post here, but IMO 3 out of the 4 names you listed would be considered "Pigeon sh*t" by most.
I like RelayTraining, but with 28,000 results I wouldn't invest too much in it. How long before a name like that sells? I don't think anyone here can answer that.. Domaining is a numbers game, the more domains you have, the higher potential you have of making sales, the same applies to quality, But with very HIGH quality domains that most of us cant afford, you don't need a large number of them to attract buyers.
You asked about my first domain sale, I had roughly 50 domains before I made my first sale, and that was after 3 months, I didn't use that money to pay bills or buy a designer purse, I re-invested that money in more domains, and when I sold another, I re-invested it again, and over time the domains I was acquiring were better and pricier, then came my first really big sale of $30,000, this was shortly after my first year in domaining.
What I suggest you do is, build UP your portfolio with better quality domains, desirable domains that end users want.. And when backordering a domain, don't settle for pigeon sh*t, it's better to spend $1000 on one good domain than $1000 on a dozen crappy ones.
Once you have your portfolio built up, sales will likely come your way.. Domaining is NOT a get rich quick business like so many newbs believe, you need to put A LOT into it before you can even think about get something out of it, your NOT even there yet, NOT even close with your 4 domains.
Good luck!