Basements are blooming expensive, however now is the time to do it rather than regret not having all that extra space for a cinema, wine cellar, pool hall...once its built, you could potentially have a huge area there, you'll need to shutter up and underpin round the existing house though unless you are going to go under there too.
Biggest expense will be getting rid of all the muck, do you know any local farmers with a hole to fill in? Work on getting rid of twice as much as the actually cubic meterage and you won't be far wrong.
Biggest expense will be getting rid of all the muck, do you know any local farmers with a hole to fill in? Work on getting rid of twice as much as the actually cubic meterage and you won't be far wrong.