How does Reputation affect gameplay?

It makes other sims text you a lot, that's for sure.

I've been playing a lot of sims but mostly I'm noticing opportunities to get a better jobs out of the blue for both good and bad reps. The jobs will align more with the rep of course.. like the criminal career can be offered to bad rep sims, and more. You get offers for blind date set ups. My bad sim got set up with Judith Ward.. I had fun with that. Otherwise none of my sims that I'm driving to a good or a bad rep really have much fame so I haven't started on what the fame points will do there. Oh and when you meet new sims the rep affects that.. my bad sim is having to work at it a little more unless the sim they meet is bad too.
I only played with one sim with a roommate so far and it seems to only affect individually... could be wrong there.

I'll just use my opportunity to write long texts.
Your sim's reputation may affect the starting relationship. Sims with good reputation may start at higher relationship with new sims they meet and sims with bad reputation may start at lower relationship with new sims they meet (unless that sim also has negative reputation or has evil or mean traits).
From the great or awful reputation, you will start getting a lot of text. The texts may offer your sim a new career in higher level (criminal career for sims with awful reputation, all the other careers to sims with great reputation), give your sim chance to meet new sims and may set your sim up for blind dates (with similar reputation with awful reputation), and sims with great reputation may get texts asking them to donate money (will gain your sim some fame) and sims with awful may get offered some money (that other sim got in an illegal way). At that level, your sim will also have easier time getting the job performance up (for sims with awful reputation, this only applies to the criminal career).
The top levels are pristine and atrocious reputations. At these levels, other sims will react to your sim's presence. Sims with pristine reputation will have easier time mending negative relationships and sims with atrocious reputation can bribe other sims for friendship and bribe their bosses for job performance boost (easy way to get a promotion!). Your sim may also throw one of the new social events. Sims with pristine reputation can throw charity benefit parties, where the goal is to collect 10,000 simoleons by asking party guests for donations. Sims with atrocious reputation can throw lampoon parties, where the goal is to roast the guest of honor (one specific sim you choose) until he/she is in Hysterical emotional state (the point where that sim can die by laughter). The rewards of these parties are reputation changes, fame, and a trophy if you got the gold in these parties. Sims with great or awful reputation may get invited to these parties.

Like known, the reputation changes when your sim interacts with others when NPC sims are nearby. However, the reputation changes more when your sim reaches a new relationship point with another sim (even when nobody is nearby to see it).

In short: Positive reputation is good if you want your sim to be popular, negative reputation is good if you want more money.

Here's a bit of info on the reputation feature.

http://simscommunity.info/2018/11/15/the-sims-4-get-famous-reputation/

"EgonVM;c-16881667" wrote:
I'll just use my opportunity to write long texts.
Your sim's reputation may affect the starting relationship. Sims with good reputation may start at higher relationship with new sims they meet and sims with bad reputation may start at lower relationship with new sims they meet (unless that sim also has negative reputation or has evil or mean traits).
From the great or awful reputation, you will start getting a lot of text. The texts may offer your sim a new career in higher level (criminal career for sims with awful reputation, all the other careers to sims with great reputation), give your sim chance to meet new sims and may set your sim up for blind dates (with similar reputation with awful reputation), and sims with great reputation may get texts asking them to donate money (will gain your sim some fame) and sims with awful may get offered some money (that other sim got in an illegal way). At that level, your sim will also have easier time getting the job performance up (for sims with awful reputation, this only applies to the criminal career).
The top levels are pristine and atrocious reputations. At these levels, other sims will react to your sim's presence. Sims with pristine reputation will have easier time mending negative relationships and sims with atrocious reputation can bribe other sims for friendship and bribe their bosses for job performance boost (easy way to get a promotion!). Your sim may also throw one of the new social events. Sims with pristine reputation can throw charity benefit parties, where the goal is to collect 10,000 simoleons by asking party guests for donations. Sims with atrocious reputation can throw lampoon parties, where the goal is to roast the guest of honor (one specific sim you choose) until he/she is in Hysterical emotional state (the point where that sim can die by laughter). The rewards of these parties are reputation changes, fame, and a trophy if you got the gold in these parties. Sims with great or awful reputation may get invited to these parties.

Like known, the reputation changes when your sim interacts with others when NPC sims are nearby. However, the reputation changes more when your sim reaches a new relationship point with another sim (even when nobody is nearby to see it).

In short: Positive reputation is good if you want your sim to be popular, negative reputation is good if you want more money.

Wow! That was a really comprehensive description of reputation. Very helpful. Thanks for posting, I learned a couple new things :)