I rent a similar size barn 130ft x45ft inc limited leccy for about £250 per months no extra bills. If I were you I would build a strong room in there, I learnt the hard way by being nieve about tools etc. I had a break in just over a year ago I lost £8500 in snap-on tools and had my land rover and group a escort stripped in one night . I now take my tools home every night and have bought an alarm witch has a sim card in it and rings or texts five saved numbers until you reset the alarm. It's hard to get insurance on theft from farm buildings. It's still the best value for money tho without the brake in.