It took BT about 3 months to turn on the phone when we first moved in our flat, Why so long? well apparently the geniuses, no word of a lie, kept calling our "future" phone number, the one we'd have after they turned on the phone line, to confirm, but surprise surprise no one answered, and so they canceled. The first bill was nearly £250, £63.48 for "line rental", one off charge of "£106.37", £4.50 in "payment charges" which is the charge for having to process payments to them, the cost of calls £38.40, 4 calls totaling 2 hours, 6 minutes and 4 seconds, and of course £31.32 in VAT. (the bill is on my desk, I haven't memorized it =p)
It took 4 months to get internet turned on, we ordered it last week of January, and we finally got it turned on today.
Heat and hot water only took a little over a month.
But yea no deposits, except the internet may make you pay for the year upfront, depending on which provider you go with.
BT sucks, avoid them if you can. Best of luck!