Hey Saurav,
Go through this link for the packages of Rajasthan available on Tripoto :
https://www.tripoto.com/tour-packages/rajasthan
It would be more budget friendly if you plan the itinerary on your own and go by yourself.
Happy travelling!!!!
Mount abu and Udaipur can be covered in one go but Jaisalmer is on another side. If you want to go Jaisalmer, you should include Jodhpur and Bikaner in your itinerary. Still if you want to go Udaipur along with Jaisalmer, it'll be better that you hire a car and then go and explore according to yourself.
As we know, the Golden city(Jaisalmer) in Rajasthan famous for their camel safari, Jaisalmer forts, Salim Singh ki Haveli, Historical Monuments and many more places and things to explore.
I would recommend exploring by yourself becoz this how you learn during traveling to some new places.
But if you are willing to get a package Here is more information about the package
https://www.pleasureholidays.net/rajasthan-tours/udaipur-mountabu-jodhpur-jaisalmer-tour-7-days
Good Luck!!!
Happy Travelling!!!