People seem to be being mislead here...
The RTB guidance says that for new tenancies where a market rent can be applied to look for 3 tenancies on the rent register with recent start dates (within 3 months). I would not limit myself to the first 10 they show if you can demonstrate they are not recent.
A tenancy having a recent start date
does not mean it currently gives you an indication it is in some way a useful "market rent". Most properties on the register with a recent start date currently relate to properties where tenants have moved out and new ones have recently moved in. That starts a "new tenancy", but the rent permitted would be the same (give or take 1% or 2%) as much older tenancies anyway because the "new tenancy" began under the suppressing RPZ rules.
There might, occasionally, in the odd selection of 10 sample tenancies from the register be included a rent relating to a property
recently let for the first time. That would currently be suitable to be used as an example of actual market rent. But those will be very uncommon unless you are trying to rent out a unit in a recently finished BTR development.
In a year's time, a tenancy at that point on the register having a recent start date will mean the landlord will have had the opportunity to "re-set to market". But you don't exactly need to be a professor of economics to work out that with landlords having been more or less forced to set rents for recent tenancies in line with historical, and often deeply discounted, RPZ controlled rents in circular fashion, those rent prices are not going to be "market rents" in any meaningful sense either.
Ironically, also thinking forward to a year's time, even a property having recently been let for the first time will no longer reveal a proper market rent - because the RTB are insisting that even property never rented out before must use the same process as a property being "re-set to market", ie effectively matching historical, suppressed rents. A supplier of rental property to the market won't be able to advertise the property, get hundreds of responses eager to take it, and agree to rent it to the selected tenant. The RTB will say it is "above market rent" because it is higher than all the 10 historical, RPZ influenced, examples.
As for supplying additional evidence - well you can't compare your smart, modern interior to the examples on the register (which could be absolute dives) because you don't know anything about them other than things like how many bedrooms they have, and a rental valuation from a lettings agent is (if accurate) likely to be far higher than the ten examples from the register - and they might prosecute you.
Not exactly a confidence inspiring atmosphere likely to draw in badly needed new supply the Minister claims to want.