To think you only get a specialist school if you have a lot of money to throw

I got mine into a specialist unit within mainstream.

Mainstream school didn't work out. Then we home educated for a while.
In the absence of school to make a referral- I persuaded the home education person at the council to do it.
The council's Area Integration Team considered his case and agreed to place him there.

I'm not sure, tbh, why it was so easy for me. We're in Scotland so the system is different. There's no need for an EHCP, for example. Which has advantages and disadvantages.
I think my slightly unorthodox route might have helped. Since home education officers have an interest in getting kids back into school. Whereas perhaps school SENCO's have pressure not to make too many referrals.
I wouldn't recommend anyone else follow my lead. Obviously if it didn't work out I'd be stuck home educating! Which, tbf, I would have been quite happy to do.

I think it did also help that the council were aware I would have gone to tribunal if needed. I wouldn't have needed a solicitor as I'm quite confident with law, having worked in a different legal field. Education tribunals are theoretically designed to be accessible to lay people so I was certainly up for giving it a go.

I feel for you, OP, and I hope you manage to get your situation resolved.
If you're in England or Wales, there's a facebook group called SEND Education for All, which seems good.

If you're in Scotland, I found the Enquire helpline very useful.

We didn't, moving from mainstream primary into special, but this was in 2018. I'm sure it's harder now, but I do know plenty of people without loads of money who have been through it more recently. Don't be put off

I work in a SEN school in Wales

I can assure you a lot of theparents do not have loads of money to throw at anything.

Every case is different.
We have PMLD pupils who have been in our nursery since 3 and the private SEN nursery before that.
Mainstream was never even an option
We have pupils who did fine in main stream primary but the transfer to us for seniors.

Then we have some who come in from mainstream who should've come sooner.

The reality is there just aren't as many spaces as needed.

We were lucky, no fight. DC has severe learning difficulties and autism.

By having a severely disabled child for which mainstream wasn't the remotest option. We still had to defer him a year until there was a place but no money changed hands and it was all very straightforward. I don't consider myself lucky to be part of this cohort, which is the majority of his school.