Hey 
judging by your username you've been around for some time ;). Thanks for pointing the changes out.
When did they change the base API url ? Didn't catch that change at all.
Whats up with sm_update_rental_price ? Is it a new operation type ? Any advantage ?
Edit: filtering the prices by level is a good idea. although you could also look into the for_rent_grouped endpoint. saves a LOT of api calls. It's a bit delayed, but i haven't noticed a large difference in rental revenue between the two.
RE: Programming Tutorial: Renting your splinterlands card collection with python