Section 21 - complicated (I think)

[Isthiscorrect]

So, we are selling what was our family home. We have lived overseas for nearly 20 years and the house has been rented for the entire time.
The current tenants have been there 15 years. We advised the managing agent we are selling (divesting all our uk assets) and asked them to serve a Section 21 (giving almost 3 months notice). The agent said let me speak with the tenant and come back to you, and do you have a price in mind if they want to buy. We suggested the tenant make an offer they felt reasonable (we have spoken to 3 local agents in Nov 24 so have a good idea of the price).

Agent came back tonight and said they have offered the price we were looking for (not that she knows what that is). And that the documents for the section 21 would be sent next week.

So my questions are,
If we agree to sell to them I assume we still need to serve a section 21 in case something goes wrong and they can't/don't buy and we need them to leave.
How long is reasonable to allow them to sort a mortgage etc given this is not what they were expecting?
Again I assume we still collect rent in case things don't proceed or until the sale is complete.
What happens if the sale doesn't complete for say 4 months, does the section 21 expire on its original date mid April? Do we need to serve it again? When would that be?

I'm not sure I trust the agent to be on my side with this so any advice gratefully received.

Serve the s21 now, no reason for delay.

Accept the offer to buy but state you will continue to market it.

Don't put all your eggs in one basket waiting on them to buy or move.

I think you’re right to be wary of the agent. Bear in mind that their fee income will stop when the house is sold, so they may well try and string things along. There’s no reason not to send the S21 straight away and put the house on the market with one of the agents you’ve spoken to. Your tenants should definitely be able to get a mortgage sorted out within a 3-month timescale so I’d make that a condition of your accepting their offer, ie completion to take place on or before 27th April, assuming the letting agent gets the notice to them on Monday. It’s worth asking the agent what the price is that they think you’ll accept, if you haven’t already given them a price. Also are they expecting a fee on the sale? Be firm with them because they’re very likely to spin you a story.

Does the tenant have a current valid gas safety certificate?

Have you checked your letting contract with the agent to see if you will owe them a sale fee for selling to your tenants? I know some agents put clauses like that in.

Thanks for your advice. Yes the tenant has an up to date gas certificate. The section 21 will be served next week.
I spoke with the agent this morning. She says she will come back to me by next Wednesday to let me know what progress she has made with regard to checking the validity of the purchasers documents and if the offer is proceedable.

My final comment to her was and how much is your cut? Again she said she'll come back to me. I'm hoping it will be less than the 1.5% it says in the contract. Probably just wishful thinking but I can hope.