30,000 NRs / month is not a bad deal. it's a good amount of money. in fact, it's lot better than what engineers working for government earn (not counting ghus). and since you have house in kathmandu, that's even better - no rent, and best of all - you'll be with your family! and your bank will probably give you a bike for transportation. if they don't ask for one because it's normal. even a +2 graduate working as/for a broker gets bike these days. you'll be living a good, respectful life earning good money. but before you jump in, make sure the bank is good/stable one.
well, you'll miss beaches, drink parties, and stuffs like that here but that's getting more common in Nepal these days, besides the beach of course! you'll soon make friends. if you can't get a job you like here in the States, there is no point in staying. grab the opportunity and go home. try to negotiate salary too. good luck!