If you have to pay for the connection to AC - that's okay, you just keep that in mind once you sell the apartment (if ever). I think the worst thing could be to jump out now and lose the downpayment (that is certainly more than 130K right?)

Probably you bought it as a long term investment. You can look at it differently: this one time charge will be distributed on the full term of your ownership (let's say 20 years), so in the end you'll have a couple of hundred riyals as AC connection charges per month...