FOI - GLA Property Management Fees data

I’m interested in any data you may have around fees paid by leaseholders to property managers, mainly with regards to service costs and management fees. I found the following report from 2012 on your website:

https://www.london.gov.uk/sites/default/files/gla_migrate_files_destination/Highly%20charged%20report%20March%202012.pdf

In it you have statements such as “we charge a management fee which is 15 per cent of the leaseholder’s total service charges with a minimum charge of £50 capped at £500” and “ARMA (the Association of Residential Managing Agents) estimates the average service charge bill to be around £1,800 – £2,000 per annum in London, although they can reach up to £5,000”  – this suggests that you do have some data around this. Would it be possible to get that data and ideally a more up-to-date set of numbers than 2012 ones?