Craigslist is all relative to where you are, what you look like, who you are after, and your standards.
I'm a bi guy, mid 40s, and a heavier guy. Nothing about me is particularly exceptional,other than I can pass for mid to late 30s (I guess that's something?). I don't have a monster dick. I'm somewhere between 5.5 to 6" erect. I'm college educated, but I'm a bit introverted at first.I'm heavy set, but I don't think I'm hideous, unless heavy set is hideous to you. We all got what we are in to. Before I got heavy, I was told I was reasonably handsome. Neither here nor there. I am what I am: an average Joe.
Anyway, I've viewed CL in the Phoenix area for the purpose of (attempting) to meet for casual sex, or basically just because I am bored and in some ways, a form of amusement.
Here are my results, as honestly as I can give them (yours will definitely vary):
First off, when it comes to posting my own ads, I quickly found that when I posted ads in M4W, or M4T, I got nothing but spam. So, I quit that shit. For M4M ads I posted for, I learned quickly that what worked for me is to just respond to ads because even if you look like sumo wrestler and post an ad, you will get a shit-ton of responses and spam, and let me tell ya, there are some really weird people responded to my ad that I was sure if I met, I would be axe-murdered, based on what they wrote.
And NOBODY reads your requirements, either. It was in posting M4M ads, that I got some measure of a sense of what women go through when they post ads for online dating, and all I can say is this "To women who post ads and aren't scammers and just looking for a guy, as a man, I feel for ya! You ladies take a lot of shit from guys!"
Second, I highly recommend that if you want to meet anyone from CL ads, have a throw-away email account set up (IE Yahoo, or hotmail, or gmail) that you use only for CL.
Third, at least have a few emails back and forth before even giving out your number, let alone meeting off line. That way you can sus out the weirdos. If you do decide to meet someone off line, do it in a public place, first. Especially if you are a girl, but even if you are a guy, too.
On W4M ads:
I've tried this off and on since 2005ish, and just basically gave up on it around 2009. Out of the dozens or maybe even scores of adds I responded to, I'd say easily over 90% or more are scammers, women looking for sugar daddies or just a free meal or something, or hookers (you always know this if they are asking for "roses" or "hugs" or such). The remaining ads that are actually posted by women that I actually got a response from, were almost always either druggies, straight up crazy, a few were single moms, or women with insanely high expectations (IE Adds that are like I'm a 35 y/o BBW, 4' 10" 350 LBS, have 5 kids, live in a double-wide with my parents, have no car, but you must be 6'1", look like Brad Pitt, degreed and drive a Bently).
In all my time, I actually only met 2 women off line. One just ended up meeting for dinner, then the bar, and then had a "friend" call who "needed her," and didn't offer to pay even the tip. That experience made me question myself, and made me wonder if maybe this woman was following my third point above, which was a blow to my ego,if that was the case. But I concluded it was more a case of her just looking to get some free meal. She gave no indication she didn't like me, and we went to two seperate places. I would think if she was creeped out by me or just wasn't a match and wanted to jam, she wouldn't have actually driven seperately to the second place, a bar, and meet me there.
The other was a BBW (I have nothing against BBWs, in fact, I like all sizes of women, just depends on the individual), and we hooked up several times. It was actually fun. She was a nurse that worked crazy OT hours, and nights. I might have even considered something more serious, but it was just about sex. She ended up moving out of state.
My conclusion on W4M in the Phoenix area is unless you are rich, and/or are a very attractive man, is very difficult. Impossible, or nearly so, if you have high standards. Basically, if you are an average looking guy, not a very viable option. If you are a guy like me, probably close to impossible. If you are a woman, you have your pick, though.
On T4M ads:
While I am bisexual, it took a long time before I was comfortable with that fact (really wasn't until my late 30s). Starting around my early to mid 30s (not sure exactly when), I started watching transgirl, MWM, and gay porn. Starting around 2008 or 2009, I started looking at transwomen ads, mostly out of curiosity at first, then started responding to ads not long after with the intent to try to meet someone. I had responses but every one of them literally ended up being pay for sex situations, which I never acted on. Largely, though, I came to believe that not unlike the the W4M ads, many cases you are looking at scammer postings, maybe 50% of all ads.
There did to seem to be more "real" transwomen compared to the W4M ads VS fake ones, but the vast majority were sex for pay, maybe as many as 80% of the ads posted by real transwomen actually living in the Phoenix area were sex for pay. There were some who did reply back to me that weren't pay for sex, but most cases I wasn't the type of guy they were looking for, or something about what they wrote seemed off to me, and I decided against responding back, let alone meeting them (like they may have been high when they responded). The rule of thumb I discovered pretty quickly was the younger and more a transwoman looked like a CIS woman, the more likely the ad was fake, or it was someone doing sex for pay.
My conclusion on T4M ads in the Phoenix area, probably slightly less difficult to actually meet someone, but you had better be a very attractive guy to compete with the hundreds of other guys responding to each ad. Guys like me, very tough, if not impossible. I pretty much gave up on it, and only look at the ads from time to time for entertainment. If you are a transwoman, pretty easy to get laid, if that is your goal.
On M4M ads:
Around the same time as when I started looking at T4M ads, I started looking at M4M ads. Here is where a bi or gay guy can get sex. Rule of thumb is the younger and thinner you are, the pickier you can be (shocker, huh?

). It's harder for someone like me, than an extremely attractive guy to find someone, but not that bad. You just have to adjust who you are looking for, and you have to do some due diligence, once you get a reply, whether you are posting or responding to a post. When I was looking at ads from guys in their 20s or early 30s, usually, I had no luck even getting a response, unless they were just looking to collect dick pics. I have found that it's probably 65% bottom guys, 35% top guys, in the PHX area, and ads looking for BJs being a good portion of the ads.
What I found with the M4M ads, whether I posted is there is a good number of those who respond that once it gets down to asking for numbers, or setting up a meet, they chicken out. I'd be lying if I said I never did that, too, when I first started trying to meet guys for sex on CL. Some guys who are still not comfortable being bi or gay do that, and I was no exception at first. I guess that is just part of doing business and it happens.
I have the best luck actually hooking up with guys who I guess can be termed chub or bear, who are around my age (IE 35-55). Since 2013 I think I met around 20 guys, give or take several, for sex. In most of my encounters, it was either mutual HJ, I got blown, or topped. I tried bottoming, wasn't into it, and blew a few guys, but the ones I met at least, really just wanted to bottom or blow me, with no reciprocation. Except for 2 cases which was with the same guy, I always use protection no matter what we do, save for HJ.
Anyway, there you have it. Hope that is useful to someone, somehow.