Tourist visa

[Mt1505]

Dear Sir/Madam,
I am applying for standard tourist visa for my father in law and mother in law as my wife is 8 months pregnant. We have a six year son as well to look after. We both working full time, my wife has been working fir nhs for last two years and I started working for my company since February 2025 and started taking salary from my company 15000 gross salary a year from August 2025 and will take dividend in the end after submiting the omoany accounts. Prior to that, I was a contractor earning around £70k per annum.
I would like to sponsor my inlaws. Please advice 1.what documents do I need?
2.How much saving do we need to have in our bank account as we both earns around £3500 a month, out of that we pay £2250 a month towards mortgage.
3. Most importantly, my brother in law ( my father and mother in law's son) has have around £6k in his saving account for the last six months, can we show that as a finance support
4. Will my two months payslips would be enough to support the application? However, my wife could provide more than six months payslips if needed.
5. Any other advice to support the application
Thanks
Kind regards
MT