Paying late for new window

[TravelInHope]

I had a new window installed recently in a top floor flat that I rent out.
The fitter was doing some maintenance work on the block, and contacted me through the management company in March to say it needed replacing. I believed him as I wasn't too surprised, and knew some of the windows were in urgent need of repair or replacement. (It may not have been urgent but it will have needed replacing at some point).
I paid half the amount in advance, with him saying the work would be completed in April. However despite repeated requests, it has only just been done last Friday, literally 6 months late. He has now sent an invoice for the remainder, and has already chased me for payment.
The bill includes £300 for hire of a cherrypicker, which has actually been on site all the time for the other work. I did agree to this at the time.
What would you do? Obviously I will pay the bill, but I am in no hurry to do so, not least because I can't easily inspect the work for a few weeks.
I feel some sort of compensation for the delay is in order. Would I be unreasonable to request that he deducts the £300 cherrypicker cost? Or would you just pay up and move on?
For those that are interested in such things, the total cost is a lot more than a months rental.

Don't be a dick, he's done the work, if you can't check, that's your problem

Pay the invoice asap

"The bill includes £300 for hire of a cherrypicker, which has actually been on site all the time for the other work. I did agree to this at the time."

Can you clarify this? Did you agree £300 or just that there would be a charge for the cherry picker? That does sound steep to me, but if you agreed it I don't think you can go back on it now.

Builders do things in their own sweet time and that is just the way it is these days. Frankly you are lucky he didn't charge you even more, because I am sure the materials would have gone up in those six months. It matters not a jot that the delay isn't your fault.

You need to pay the bill. You are not achieving anything by not paying it straight away other than a sense of self satisfaction at inconveniencing him because you feel he let you down.

He still has bills to pay and if he is the go-to man for maintenance on your building, you really don't want to be pissing him off. It's not like we have an excess of skilled tradesman lining up to do small jobs in the UK at the moment.

Ask your tenant if they are happy with the quality of work.

He used my initial payment to buy the window, which he has had sitting in a shed for 5 months.
the estate management company are very unhappy with him, for this and other reasons, and won’t be using him again. So I’m not bothered about pissing him off.
the management company suggested I seek some compensation for the 6 month delay, so surprised everyone else is relaxed about it.
the tenant may well be happy with the work because he is moving out shortly. I need to do a close inspection of the fitting which I can only easily do at the new tenancy.
the figure for the cherry picker was not itemised, but appeared at £300 in the final bill.