Ok I am a tad confused about a few things:
"Am I allowed to choose an empty lot and place a rabbit hole on it to get access to the new career?" The answer is no but aren't you allowed as it says here :"When I get a new expansion, can I place the new buildings into my town or do I have to wait?" Answer being yes. Wouldn't that include new career's and therefore you would be placing a new career lot on an empty one. I am kind of confused as I understood you could place career lots/ rabbit holes on an empty lot. Wouldn't there always be a copy in the bin.
In the list of lots you gave at the end you say you can give them a Lot Destination Change. Does that mean only moving/adding them if you are playing that world? Or they are free to add to any world.
Can I change an empty residential lot to an empty community lot, then place something on it?
What classifies as an small park and undesignated lot?
Once a private lot is changed to a resort can it be changed back? Also when buying your property for each immortal is that considered a private lot and can be changed. Or is there no option to change it into a resort?
An example to make sure I am understanding this right:
When deleting the horse center in SV if I wanted to replace it and no lots were open I would have to either 1) make a new lot 2) Move something to another lot and place it. Or is option 2 not allowed?
1. The difference lies in what you are placing. The best example I can think of is in Late Night's movie career. In the community lot bin, there is a 64x64 lot for Plumbbob Pictures Backlot (or something like that). That one is ok to place.
However, if you go into build mode on an empty lot, and access the community lot items section, you will see actual rabbithole objects - the LN rabbithole of the movie lot an object that requires a lot of at least 40x40.
Placing the lot itself is ok. Placing a rabbithole object onto an empty lot is not.
2. I don't understand this question - but I'll take a stab at it. Certain lots can have designation changes. Usually when an empty lot is added to the world, it's added as a residential, but can be changed to a community lot. All other changes, see Rica's note.
3. Which leads to yes, as long as you are placing a community lot, and not a rabbithole object.
4. If you hover over the purple lot marker, it'll tell you what it is. Undesignated is usually a blank residential. Small park will usually say so.
5. I don't know the answer to the first part, but no, it's not a private lot. You need to buy a building (one of the pre-existing rabbitholes, or a rabbithole placed properly), and a property, which is still community access, and upgraded accordingly - such as a gym, or a tavern.
6. And that is correct, either method. Or, just go without the equestrian center.