Il give you some advice anyway! lol
Firstly there might be a reason why there was no Aerial... Is it a new house?? Surrounded by any obstacles etc? Did the previous people have Sky before?
Some places in the country really cannot pick up a decent Digital Terrestrial signal (i.e normal aerial) as the signal is not strong enough from "some" main transmitters.
We has sky in our place and I recently brought a High gain bunged it up in the loft (most places can get away with having aerial in the loft). My normal TV signal is fine and dandy but our Digital Terrestrial signal is not strong enough.
This meant boosting the signal but not with a normal signal booster but a masthead Amplifier. To give you an idea on price this is a variable one (much better as you can adjust it to get the signal how you want)
http://www.screwfix.com/prods/26562.../Labgear-Variable-Gain-Masthead-Amp-Kit-4-Way.
So lets say £20 that a Tv installation company might charge for a masthead amp.
Aerial no more than £15-20
Labour?? Id say 1 hour maybe 2 MAXIMUM at £30 (max!) per hour for 2 points maybe 3 = £60 (this price should also include all ancillaries like cables, tape, screws etc etc)
Total £100 Max to get an aerial with up to 2 points installed.
Remember that if they do other points then they might have to run cables = extra cost. If yours is a new place there's a chance the Electricians already ran cables up into the loft (this is the case in 90% of houses I have visited!) so this will help keep installation prices down from whatever company u get to do it, make sure you mention this or your quote will take into account they are to put the cables in and you'll be charged whether they fit them in or not! (lots of cowboys in this trade im afraid!)
Watch out as places might quote they can do it for £100 then they add on the price of cables, tacks etc etc and the price goes up.
Sky is an ok bet if your willing to pay the monthly fee as Griff said.
Also your dad possibly paid for one Aerial split to 2 bedrooms (using the masthead amplifier method I mentioned above) Nowadays there is no need for an extra aerial with all the amplifiers around (if he did have 2 then apologies!)
People think you can just buy a £10 aerial, bash it up and "jobs a good un". Sometimes this is true if you are in a VERY good signal aerial. Unfortunately this is not the case most of the time and that means using things like the above which puts the cost up.
Sorry for the essay!
