I know of the commonly cited rules for third tones, which are the following (copied from somewhere else, so excuse the grammatical errors):
"When word with the 3rd tone is used alone, or used at the end of the expression, it's pronounced as the original tone, i.e. the 3rd tone. e.g. 雪, 滑雪.
When two words with the 3rd tone are used together, the 1st one is pronounced as the 2nd tone. e.g. 老虎, 海岛.
When word with the 3rd tone is used before other words with the 1st/2nd/4th tone, it's pronounced as the 半三声 (only the first half of the 3rd tone, without the rising tone part). e.g. 卡车, 草莓.
When three words with the 3rd tone are used together; If the first two words are closely linked, i.e. 2+1 construction, then the first two words are pronounced as the 2nd tone. e.g. 草稿纸, 古典美. If the last two words are closely linked, i.e. 1+2 construction, then the 1st word is pronounced as 半三声, the 2nd word is pronounced as the 2nd tone. e.g. 米老鼠, 老领导."
What I'd like to know is:
A third tone should generally be pronounced as a full third tone whenever it is the last syllable in a word/expression. Is that true even when speaking quickly, meaning the final third tone of a word is quickly followed by a non-third tone? Or should it be a half third tone in that case?
What about the following examples of multiple third tones: 使馆里，大使馆里，地铁里? or 米老鼠我不太喜欢？ These don't quite fit any of the categories above. How should the tones be altered (if at all)? Does anyone know the rules? None of my Chinese friends are certain so I hope someone here does.
Thanks a lot!