hello aspirant,
Here are the below best and optimum fee structure colleges .
1)LD college of engineering ,ahemadabad.
it has a rating of AAA+ offering best education .
2)viswakarma government engineering college, ahemadabad
based on GATE and GUJCET  exam college is accepting admissions and fee structure is optimum and any how fee ranges from year to year
3)NIRMA UNIVERSITY ,ahemadabad
It is one of the top 10 colleges in ahemadabad providing a highly enhanced education offering best placements to the students.
it has an good reviews by students and has an rating AAAA.
hope it will be helpful for you,
thank you

Hello

I have attached a link where you will get the list of good Btech college in Ahmedabad. Below the name you will find the fee structure/fee mentioned. Go through it to see which is within your budget: 

https://engineering.careers360.com/colleges/list-of-engineering-colleges-in-India?f%5B0%5D=sm_college_degree%3AB.E%20/Btech&f%5B1%5D=im_field_ownership%3A966&f%5B2%5D=im_field_ownership%3A967&f%5B3%5D=sm_college_state%3AGujarat&f%5B4%5D=ss_google_city%3AAhmedabad 

However, few of the best irrespective of fees are:

1) Nirma University, Ahmedabad

2) LD College of Engineering, Ahmedabad

3) Institute of Infrastructure Technology Research and Management, Ahmedabad

You' ll get the complete list: https://engineering.careers360.com/colleges/ranking/top-engineering-colleges-in-ahmedabad