Keeders,
Being a local, I can offer the following -
You don't need to enter the class A airspace (London CTR) with a SVFR to get into Fairoaks. The ATZ is Sfc- 1500 feet, and the southern portion of the ATZ is outside the Heathrow zone - it does lie beneath the LTMA (above 2500 feet). So approached from the SW-SE < 2500, you are in class G until within the Fairoaks ATZ. You don't need to speak to Heathrow at all, unless you want to transit to Fairoaks SVFR from the N or W.
Others have already given good advice - PPR, talk to Farnborough LARS, route via Guildford and Ockham. Of course, you can route "British Rail" along the Basingstoke - Woking railwayline, but it is probably easier to come from the South on your first visit.
I suggest that you keep on 125.25 until near Ockham, then call Fairoaks. Ockham is a bright yellow at the moment, whatever the flowers are! There is a very visible light-grey rectangular tower block in Woking that is a useful landmark, too - it helps to pinpoint the railwayline that you need to be at 1400' QFE by. Don't get any lower though, as circuit height is 1000'.
Note that the taxiways have changed, so your Pooleys is probably out of date. If you are landing on 24, no real change, although you may be asked to hold at the new junction before getting clearance to the apron. Landing on 06, you vacate left at the end of the runway as before but then take the first left, rather than continue straight ahead.
I'm not aware of any restrictions on number of movements, but do call the tower for a briefing.
Enjoy your visit.
SD