Certainly tickets for the Hungaroring aren’t massively cheaper than the western European races. Turkey might be a tad cheaper but you’ve got to get there first – EasyJet fly out from the UK to the airport near Istanbul Park but everyone (including team personnel!) will be getting those flights, pushing the price up.
The cheapest general admission tickets for a European race are (I think) for Monza. The town of Monza itself is on a major railway line so it should be easy enough to access from wherever you get a flight to (Milan most likely but check out other nearby airports too as rail links in that part of Europe are very good). If you were feeling really adventurous and booked far enough in advance you could do the whole lot by train (Eurostar to Paris and then an overnight train to Milan) for under £150 return. Might do that myself actually…!#
(Though if you can’t get a flight from somewhere in the UK to Milan for under £150 return then you’re probably doing it wrong).
if you live in brum, then a visit to see silverstone syd is the best option, no flights, transfers, accomodation etc, however if funds would stretch I would take in a European race, 3 days at Monza would be hard to beat, camping out at the back of the Lsemos and chilling with the locals
Monza is a decent idea i reckon. If you fly with a budget airline (Ryanair maybe) you’ll be able to get it for about £50/£60 return IF you leave it until about a month before the race to book a flight (that’s how they work….).