Leasehold on flat questions

[Rollerbird]

Have offered on a new flat.
Agent has said the owner will offer a 'standard' lease when we buy but would be willing to change it to 'suit our needs' to an extent.
I expect to get a copy in the next day or two.
What should i look out for and what might i ask to be included that would be a benefit?
Going to rent it for a while but ultimately probably live in it ourselves when we downsize and get older. (As it's in a very upcoming desirable area)
Not planning a sale (but you never know of course)

Look at length of lease. If it's a new lease you will probably get 99 years or 125 years. Both are fine but need extending when they get to about 80 years. Look at cost of ground rent and when the rent will increase. Look for service charges and who is liable for what. And look for how the property is insured.

I have 99 years (94 left now). £200 per year ground rent, doubling every 33 years and pay into a sinking fund and building insurance. All in it costs me about £650/year. I have never seen another lease to compare it to but can't imagine they will differ too much.

if you are in any doubt get a good conveyancer to check the lease.
Things to look for include:
How long is left? What are the annual charges? Who is responsible for maintenance (especially of communal areas) and insurance? Are there restrictions on pets/ working from home?
You may need freeholder permission before you can let.

I would look at everything mentioned so far, however I would also ask about everyday uses of the flat, especially if you are planning to rent it out - for example, my leasehold flat has restrictions about the hours that you can use things like the hoover and washing machine. I also have restrictions in place saying that I cant hang washing outside either my windows or in the communal gardens.
The other thing to ask about is pets - yours (or your tenants) or your neighbours. In my case someone has a cat (not meant to have any pets) and no cat flap in their front door, so this poor animal is trapped in the communal space, sometimes for hours, making a noise, not to mention its toilet habits.
I would also seek clarification on who is responsible for damage - for example if a leak originates from your property or if a leak from another property damages your flat.