yes I think you need to pay those immigration consultants.. it is their service of asking you what to put in your application. in the end, you will pay and go to vfs yourself. so doing the search here, will help you get away big costs for immigration consultants. there's been a lot of people who got their visas successfully through this forum.
do read the vfs website.. it is very helpful too.
you can use the search button here for spouse visa and you will know what are the requirements you need to put with your application.
good luck on your application
