Sweetysash,
There is a mismatch between heading of your post and the main body. To run a business marriage hall, you need to register under Shops and Establishment Act of your state. But before that you have to register your company under Companies Act.
As far as your business is concerned, you need to design the terms and conditions of your services. That includes how to use the premises, loss of vehicle parked at the parking area, accidents or incidents arising out of cables laid for the videography or photography. Now a days, drones are used for the photography. You may add clause on this subject also.
While booking the marriage hall, you may obtain signature for acceptance of the terms and conditions. No separate agreement is required.
Thanks,
Dinesh Divekar