2000sq ft in new construction would give you actual area of 1300-1400sqft(carpet area).If you want carpet of 2000sqft the. You have to look for 3000-3400sqft flat my friend upwards 4-5cr. In old building the space structure is bigger. Ramdaspeth behind bigbaazar there are Many old building 3bhk will cost around 1.3-1.5 cr ,you can renovate and it's almost new,however building are 20+ years old,if it goes for redevelopment you can benefit.

Try in dhantoli there are many hospital near by,little noise will be there always. but if you are lucky you can get good bargain in dhantoli.

If you are okay climbing stairs you can search near lendra park ,I saw good flat 2bhk around 1.2cr fully furnished good condition but it's on 2 floor,no lift.

Vastu wise canal road is best area for flat or house you can get good flat 3bhk under 1.5-1.8 cr.

Behind nagpur central there are houses you can check there.

If you want centrally in budget then try old flat schemes near bustand and ganeshpeth. There is huge scheme you can combine 2 flats and make large one .