And now back to life-and-death matters:
Rajasthan.
The new state of Rajasthan was formed in 1948 to absorb most of the States of the old British Rajputana. (Bahawalpur had been part of Rajputana, but acceded to Pakistan at separation.) Rajasthan included the former stamp-issuing States of Alwar, Dungarpur, Jhalawar, Shahpura and possibly Kotah and Tonk, and the still active States of Bundi, Jaipur and Kishangarh.
Bundi and Kishangarh used a handstamped or machine printed overprint:

(Handstamps on Bundi)

(Machine overprints on Bundi), and

(Handstamps on Kishangarh)
Bundi only overprinted its last set, although it made up for that by using black, violet and blue handstamps as well as black machine overprints.
On the other hand, Kishangarh went trawling through the stocks of remainders, and overprinted stamps from issues dating back to the 1899-1901 set. Generally, the older stamps are scarcer - obviously stocks were much smaller. Many of the more modern stamps are much cheaper overprinted than un-overprinted. The last 5 Rupee (SG 91 of Kishangarh and SG 65 of Rajasthan) mint is catalogued at £750
without the overprint, but £50
with the overprint.
This brings us to an important point about these handstamps. The expertising bodies used to refuse to certify the handstamps, and they may still do. Too easily forged. With Kishangarh, a simple rule of thumb is to compare the values of the overprinted and unoverprinted stamps to work out whether an overprint is likely to be genuine or not. (And of course, if you're in the market for a Kishangarh 1945 5 Rupee, you'd want to be fairly certain that a handstamp
hadn't been removed

)
Jaipur went its own way with the Rajasthan overprints:

The Jaipur issues could only legitimately be used between 26 January 1950, when they were released, and 1 April 1950, when the State POs were ordered closed. The lesson is obvious: beware of forged postmarks. The 1 Rupee is at £23 mint - and £275 used.
The shutdown of the State post offices wasn't quite as neat and orderly as that might suggest. Here is a quite commercial use of an obsolete Jaipur 9 Pies postal stationery envelope, with British Indian and independent Indian stamps, in November 1950 - 7 months after official closure. And still using Jaipur State cancellations, too.

Genuinely used overprints on Bundi and Kishangarh are for the most part quite scarce. Regard any used items, let alone covers, with suspicion!