OK to make things easy I can tell you more or less how much I spend on a regular trip to Madrid:
from Coimbra to Porto and Porto to Coimbra, it's 120kms, 11€ for each soo 22€ total
Porto-Madrid and back, I can normally book a 50€ flight return with Ryanair
Transportation in Madrid:
from airport to hostel, hostel to tennis, etc... normally I spend like 15€ on subway (buy a 10 ticket package)
I normally buy day and night session tickets for R2 and R3, the cheapest seats available, normally pay in totalk something ike 110€
Cat's Hostel (I love this hostel), something like 15€ a night for the cheapest bed + breakfast, maybe a bit less, normally stay 4 nights, 5 tops, so something like 60€
at the tennis center is very expensive, and they don't let you bring any food or drinks in.
So I normally starve all day.
this is sadly true. I mean, I don't starve, but I eat less than I normally do.
I probably spend like 15€ a day for food (it helps when you're a girl, small and don't need to eat much).. so 60€
I always stay until friday or saturday, so that if i wish, I can buy a ticket for QF and have one more tennis day... but I won't count that.
So in total... something like 300€? Give it a margin of 50€... so 350€
But you have to understand that I don't do luxuries, or stuff that for my parents, Lee, star are normal and necessary. Like food, during these days is basics. eat as much as possible for breakfast at the hostel,
, then a few sandwiches and ice creams during the day. And if I an sightseeing Madrid, then I may allow myself to eat junk, yet cheap, food like McDonalds, etc... also hostels, well I love them, but I am 22 years old.