Hello,I have downloaded the story progression mode now in my town (or university town) I keep getting message there are no vacant houses. I experimented with immigration and emigration settings but nothing seems to make difference as soon as I move fee Sims out the houses are taken within minutes.
Another thing I struggle is it seems like majority of the households have huge families seems like there's between 5-8 Sims in one bedroom houses. Any help would he appreciated

In a homeworld, are you sure you've already set the immigration gauge to null? It's in General - Sims - Options: Immigration and Emigration and set the gauge to 0. Then annihilate any immigrated households in your town with MasterController.
For sub neighborhoods like university, vacation and future worlds, the gauge isn't set up to 0 so you've to do it whenever you go there for the first time.

@johannshah - I think you might want to check that path again. Resident Immigration is controlled by the menu under Options:Lots. The one under Options:Sims is for the genetic pulls of NPC Service Sims and Roommates. Mod values for traveled to worlds are supposed to be inherited from the world traveled from the first time, then they become independent. The ones mentioned do not have different world-specific defaults associated with them unless you have a tuning file in place that sets them as such.

@MissAlice1 - Hi there, welcome to NRaas, and thanks for bringing your questions over here. I didn't realize when I first read them on the EA forum that you might have been talking about Uni World. That one gets managed very differently from homeworlds even before SP enters into the picture. Households of students and townies will get spawned to provide a pool of students each term, they will be larger and often not related to each other as university housemates will tend to be, and they will try to spread out among the off-campus housing rather than in the dorms and frat/sorority houses until until there is nowhere left for your own actives to live. Many of us see this. There are some ways to reserve a house or three for actives so they don't get shut out, but these have to be done either before leaving the prior term or by editing Uni World from within Edit Town before traveling there.

-- Set the houses you want reserved to type Residential:Player Ownable. This designation doesn't always stick, so...
-- Pull out the refrigerator. Inactive sims will never move into a house on their own that doesn't have one.

On the homeworld front if this is happening there as well, yes let's lock down SP Immigration as it sounds like you don't have any space for the sims you've already got. On City Hall or an in-game computer,
NRaas > SP > General Options > Options:Lots > Options:Immigration/Emigration > Immigration Gauge > set it to 0 or to a really high number that the pressure value can never reach, like 500.

As to how things got that way in a homeworld, yes immigration could be part of it, but there could be other factors. Are you certain these households are all new arrivals? If your sims are breeding at high rates, there is insufficient housing to support a booming generation, and there is no emigration as there wouldn't be by default, then they will bunch up more as they don't have a choice, those aging up to YA won't be able to move out on their own, recently married couples will get stuck at home, etc. all of which over time could be contributing to those overly large households.

Can we get some numbers to work with? On such a world, what is its total resident population and how many households does the town have (the homeless and service numbers don't matter as much). Am assuming you have MasterController, on City Hall
NRaas > MC > Demographics > Population > "X" to dismiss the filter

And how many residential lots does the town have, how many of them are occupied vs. unoccupied (vs. empty, which means no house is on them)?
NRaas > MC > Demographics > Lots > "X" to dismiss the filter

And what is the world's population cap?
NRaas > SP > General Options > Options:Sims > Maximum Residents > Humans > (default is 150, but for some worlds that won't be low enough)

No I don't have master controller but counting them from edit the world the number goes up to 103 spread over 36 houses. There is 4 empty
And the maximum is 150, I've changed the immigration to 1000

Was meant to be 4 empty lots

This is for a homeworld (not Uni)? So 103 sims living in 36 houses would be an average of 2.9 sims per house. Doesn't sound extremely over-crowded townwide, I was expecting the average number per house to be more like 4 or 5 from what you have described. Do you have a lot of households with plenty of bedrooms but of 1 sim only to balance out the larger ones? If so, that's where all your otherwise available housing for them to spread out might be going and maybe you can combine some of those households. Or, if you get MasterController, you can zap away some unwanted households by Total Annihilating said sims like johannshah said and then either way reserve some of properties for your own sims' use. Or you could build/place pre-made residentials on the 4 empty lots and reserve those, again such as by designating them as Player Ownable or not supplying a refrigerator.

On the population cap, if you were to change that to let's say 100, then in addition to stopping immigration (which you have already done), no inactive sims in town will have babies or adopt on their own until some resident sims die off or move away to bring things under the cap again. Existing pregnancies will not be affected and player-directed sims can still adopt and Try for Baby. At something like 110 or 115, the breeding will continue but only up to a point. But at 150, sims will continue to have plenty of kids on their own. MC on the demographics function as described, would tell you how many sims are currently pregnant and how many are in which age stages, if your world is temporarily top-heavy on elders, what the next generation will look like when the current babies, toddlers, and children age up, etc.

Does any of this help you take better control of this world?

Yeah that's because I gotten rid of some to make empty housing to move my Sims to a different house and now the houses I emptied have been occupied by now single Sims and quite a few elders died recently in my game. I will try your suggestions and see how my game works out. Other than that is there nothing to not stop but slow down the Sims moving the houses and occupying empty ones ?

Sims will move around and spread out like that given the chance if they can afford to (maybe these households have too much cash on hand for their own good?), if they do not like who they are living with, or if their current houses do not meet their needs -- not enough beds/cribs for example, since sims cannot purchase their own furniture. If they can afford it, a single sim would have no feelings of remorse over moving into a 4- or 6-bedroom house that a larger family could make more effective use of. I use SP Money and my inactives are taxed so heavily (as are my actives) that not every household in town can afford to move around and split up like that.

On the sims splitting off merely because they don't like someone whom they are living with much, that can get a little out of control at times.
NRaas > SP > General Options > Options:Households > Broken Home Move > (try False for a while), although that will also stop a sim in such a situation from moving in with friends/relatives in a different existing household.

The most effective way to slow down the spreading out though, especially as teens age up to YA and want to move out on their own if they can afford to, is to not give them enough viable housing to spread out into.

Ok it all makes sense
Wondering if you could help me with the pop us stories
I disallowed stories in general-sims-stories
I set stories false in town options I set stories allow summary false in town options and finally in general options stories I went to disallow story and ticked them all and I still keep getting pop ups that this sin got this job or that sin improved that skill...

On City Hall or an in-game computer, NRaas > SP > General Options > All Stories > (set to None or whatever subset of sims you do want to see them on). You don't have to disallow stories on particular sims or by particular story subject unless you want to.

Whatever changes you make there or in the other places you mention will take a while, could be a couple or three sim days, to take effect. The stories already in queue have to run out before the changes can really take effect.