Help us get our dream house

Let me introduce ourselves
I am a single mom of an amazing 4 year old strong willed beautiful daughter.

we both have been having health issues for years.
I have myopathy in all extremities, which means I have loss of muscle strength.
this makes every day life extremely hard.
I work as nurse, on assignments.
my condition limits how many hours I can work so unfortunately I can not pick up extra shifts for extra income.

my daughter was diagnosed with sensory processing disorder and is currently being evaluated for ADHD, she also suffers from extreme fatigue a lot and has ongoing issues with pain in her legs , which doctors have yet to find a diagnosis for .

We are currently living in a appartement on the third floor

Unfortunately we have to move out in 3 months, so I have been frantically searching for a new place to live, but the market for affordable housing is extremely tight.

I found a great house not too far from our current location and it ticks all the boxes.

It is ground floor, which means No more walking up a lot of stairs, so less pain and struggling.
It would also be a lot safer since little one sometimes does very dangerous and impulsive things (due to her processing disorder),like hanging out of windows too far, wanting to climb on the balcony railing and such.
So I have to have everything locked like a safety fault, even on the hottest of days.

So a house at ground level would eradicate all these dangers.

The problem is;The landlord wants 3 months of rent in advance, and as a single mom who struggles anyway, I do not have that kind of money laying around.

I know everybody struggles nowadays, but any help will be immensely appreciated.