Let for 2 to 3 days a time – HMO licence required?

I think the danger here is if one of the tenants ever considers this to be their main home. Then you would be caught out without and HMO licence.
Other advice I have seen is to contact the council, which you are doing at the moment to see what their selective licensing rules are in the area as these are different to standard HMO legislation.

Sounds like you are utilising the property as an Airb&b type let. Not an HMO but certain fire regs etc would still apply. Hopefully your meeting will be constructive!

With regard to unannounced visits, under the Housing Act 2004 section 239(7), authorised Council Officer's have the power to enter and inspect premises at any reasonable time to ascertain if any offences under section 72 (operating unlicensed HMOs) or 243(3) (HMO Management Regulations) of the Act have been committed.

So in short, yes the Council Officer can turn up whenever he wishes, doesn't need a warrant to enter, or permission from the landlord.

If the property isn't an HMO you've got nothing to worry about, if it is then it's probably best to let the Council inspect and let you regularize the situation in terms of licencing requirements if necessary.

It sounds more like a guest house, so you will need to check the regulatory requirements for this type of business and ensure you meet those regulations. Probably need change of use permissions? Commercial insurances? etc.

The craze for SA at the moment, relies on a planning loophole, that allows a residential property to be used as short term accomodation, without a change of use. However, this is ONLY when the property is let out as a whole unit. NOT, as individual rooms. This requires a formal legal change of use, and all the mandatory fire regs etc.
As things stand, contravening planning law, is not a criminal offence. People in these circumstances have been known to receive a cease and desist letter from the planning department.
As you are renting the rooms out individually, you are indeed contravening planning law. So you may be told to stop. And also, as someone else has rightly mentioned, there will be fire regs to be accountable for. I'm not certain what those are, and who might enforce them/what penalties there may be.

However, contravening HMO laws is criminal, massive massive consequences, and penalties etc. Nuff said really.

Your very best bet here is to clearly evidence that no person who has been using the property could ever be classed as a tenant under tenancy law.
IE. If the "guests" are tourists, or contractors, with a main residence elesewhere.
Any guests that have no other main residence, you are on VERY VERY shaky ground, and you must take steps to rectify it. EG, eastern european/foreign nationals/contracotrs with no other main residency. You would definitely be seen as breaking the law, and be investigated.
We all wing things at times. I say none of this to judge you. It's a warning really. The risks you're taking aren't worth it, and you need to go back to the drawing board, and decide for what purpose your property is being used. Find out how to regularise it as such, and have some peace of mind.
Good luck.

Depending on where you are, the Council might have passed an Article 4 direction meaning you require planning consent for AirBnB.

Thank you for your responses. I have been able to postpone the visit for a week, if he
Does anyone know of a good property lawyer, particularly in London that we can engage on the matter. A David Gold Smith, was recommended but I can't seem to find his details.

To accomodate a contractor for a few weeks, who has a permanent home elsewhere, in a flat between long term lets, does one have to meet the same requirements as an AST I.e. tenancy agreement, gas safety cert. etc.?

I have heard of "Licences" being used in such circumstances but my enquiries have cast doubt on their legality.

Reply to the comment left by Ian Narbeth at 25/11/2019 - 11:24Article 4 Directions cannot currently be used to ban AirBNB style rentals (as it is not a change of use* or something only enabled through permitted development). Article 4 Directions can, however, be used to prevent a change of use from residential to (small) HMO.(*) in London up until 90 days only
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townplanning.london

I just hope the Council officials don't come to gather evidence and take you to cleaners for a massive fine of up to £20,000 for failing to license an HMO, and meeting all its conditions and requirements, all HMOs now need to be licensed, and have Linked Fire alarm smoke detectors, including carbon monoxide detector in the kitchen where the boiler is housed, all rooms may need 30min fire resisting doors, fire door in kitchen, individual room smoke detectors, 7 rooms could mean that you are housing possibly up to 14 people at any busy time, two per room, where they may consider the lives of those occupants as of major concern, with so many people i.e. over 5 or 6 persons it may require planning permission, you just hope the council officials will only come to advise you and not take you to cleaners, it might be a good idea not to take on any new guests for the time being until a visit is conducted on let us say an empty property, so that they do not have any evidence that it was occupied by more than two households when they visited. Do not trust these so called advisors, they can be real pain in the back side exploiting minor flaws by innocent landlords and make big headlines for themselves. They do prosecute, for offences that have been committed. So until their visit, do not take on new guests. You need to ask them what if you were to rent all the rooms to short stay guests so go from here and not from the fact that you have been renting already.