Do I get a friend or not??

Hello all,
Had our rabbit Barney since xmas day and he's a wonderful, happy little boy and very michivious. He's booked in to be castrated in about 3 weeks time as he cannot have it done before then due to a vets visit and they will not do it until he has finished some tablets he is on. We think he is roughly about 23 weeks now and is a harlequin brought from pets at home as a present so they were not 100% with the dates and ages which is great.
We have 3 dogs and he gets on well with them and seems happy enough on his own and with the youngest dog etc.

My question is
Should we consider getting him a friend to play with?
The only problem is if they don't get on we haven't got the room to have separate hutches etc, what is the likely hood of them getting on, I've read up on different posts and they say best to get a girl ??
Thanks for answers in advance.

Is he a inside or outside bun?
If you decide to get a second rabbit, a female would be better, a rescue female would be best, she will be neutered and vaccinated. The rescue may be able to do the bonding for you, but even if they don't, they will be able to advise which bun is most suitable for you and if all goes wrong you should be able to return her