Visit Visa Requirment to Sponsor Family Member

[mkhari]

Hello ~forum

I Would like to Sponsor My mother in Law for VISIT upto 6 Week
Me n My wife are ILR Holder,We both are full time working,Living in a One Bedroom Flat With No Children

We have never sponsored anyone B4
Could some one advise where to start

Do We need to write Invitaion Letter ?
Do we need Sponsor Letter? Involve any solicitor is Important
Is One Bedroom Enough to Sponsor One Person do we need accomodation sertificate?

Any other documents Required Please advise?

My mother in law is housewife and have bank account adn we regualrly send money to her

[mkhari]

anyone have experience please