Power wall build

[SharpSthlm]

Hi,
I live in Sweden and Electrical prices start to be too high and I have a hour rate tarriff from my Power provider.
I will get 35 of this batterys for free, They are 5 Years old and have been sitting as UPS power at my Work.
https://www.ecopowersupplies.com/fiamm-12fit101-101ah-12v-telecoms-batteries

So my plan is now to build a Powerwall in my house with this batterys,, but..
I am a Newbee on Powerwall stuff,, I dont know where to start or what I need to build this.
I guess I need some BMS, some charger and som switch where I can change to drive my house on batterys or on Line Power.
I idea is to use batterys some hours a day when the price is high and Line power other times..
(The price are now from $4$ down to $0 depending on the hour and day!)
Step2 is to get solar panels, but this is next years project maybe..?

So Can someone please help me where to start looking and what I need for this project?

Thanks in Advance.