C.T.
I can understand your problem.If you want a big party,does your building have a party room or pool available? That would probably be easiest locale. I think a bunch of parties would be a scene,and way more stressful.Lots of people expect to be invited,want to come&say they will,but in reality about a third of those invited will show,and usually not all at once.If you have one big party&invite everyone,just make it an informal buffet type gathering that spans a few hours and then you can kind of have people show at different times.If you put on the invite that cake&presents will be halfway thru,everyone could be there if they wanted,but you could suggest 1 your parents come early,the other at cake time.That way you can kind of keep people who may not get along from clashing without excluding anyone.Good Luck.