We spent a lot less than this. We did initial aba workshop of 3 days which was expensive then £400 month to hire an aba supervisor and did 15-20 hours ourselves. It was very hard but we showed enough progress to win funding at tribunal. Our programme was far from perfect and he did not make as much progress as he would with a more professional programme but it was still miles better than the alternative. He learnt more in a week of home aba than he did with 15 hours week nursery with an untrained 1:1.
We also tried to get him into the local mld/ autism school nursery as we could not really afford the aba, but he was turned down for a statement which led to long delays. You can start the statementing process without a diagnosis for young children with severe and complex needs you only need one overarching report eg EP - in theory - in reality you will be turned down as premature but truth is you would be turned down if you waited, we were told to wait a YEAR before applying. We didn't listen, it still took forever but at least we were in the appeal process when other parents were just starting out. It took 8 months to get a statement and 18 to get aba on the statement.Only a statement gives you legal rights you can enforce, without one you can be fobbed off forever. Look at ipsea.
My DS regressed at 2.3. I know that desperation you feel. I know it all seems urgent and I'm sorry to say that regressing won't matter to anyone but you. the professionals will not see that as a reason to hurry. To them regressive autism is still just autism. He will face the same delays as any other child seeking diagnosis and intervention. It took 6 months for an asd outreach teacher to even visit. then she did nothing of any use but gave generic advice we had long since read, tried and dismissed as inadequate.
Learning skills yourself is your best hope. Anything else will take months to materialise and then you may find it wasn't worth waiting for. If aba is out of reach then look at the local special school they often take children from 2.5.
But even the best intervention may not halt regression. Often children keep regressing even with aba - I suppose it's a biological process in the brain and then when the regression bottoms out they start moving forward. DS took 6 months to bottom out, he learnt nothing, then one day he started moving forward again and that has continued. I often kick myself for not starting aba sooner, but I actually think that as we had limited funds we started at the right time, caught that moment when he was ready to learn again and we just had enough money to get to the tribunal door. If we had started at the beginning of his regression we would have run out of money, we also saw incredible progress in those first weeks of aba which motivated us to keep going.Had we started when he was still regressing perhaps we would have lost faith in aba. You probably don't want to hear regression may last months - we found DS symptoms very volatile in those initial months, some days as you say he was changing in front of our eyes. But it may mean you have some time to figure out what to do and that these months are not as crucial as they seem. Recent evidence says contrary to what they used to think children who regress do no less well in the end than those who don't.
Caudwell charity fund aba,although their funds are well down. Cerebra fund speech therapy and a private pro aba salt can be a good place to start.
The very least you should get is portage. You can also self refer to speech therapy some nhs depts do drop ins. Apply for DLA we used that and direct payments to help pay for aba.
There have been some threads on here about online aba programmes.
There is a floor time lady in tower hamlets mind builders I think her company is called.
We completely lost our boy for many months, but now he is affectionate and loving as he ever was, he has learnt eye contact, he is gaining speech - slowly but it's there- he even lost his humour but that is back with a vengeance, he is exceptionally cheeky. It's been a long haul but I used to feel like DS had died and I was left with just a shell of a child and I don't feel that now. With a lot of hard work, day by day we have got him back.
There is nice easy read paperback called overcoming autism by Lynn koegel which is about play based Aba by a psych and a parent. It's not technical, but positive and hopeful. She says you may feel that nothing you will do will make a difference, but the reality is everything you do makes a difference. It was the first thing I read that made me feel the situation wasn't hopeless.
don't forget to take care of yourselves you are losing a child in a way and that's pretty tough but you do get through it.