I think 那附近有没有邮局？ = Is there a post office near there? Here 有 means "there is" and 有没有 ... ? means "Is there ... ?" The 那 I guess means "there," as in 那里 or 那儿。 Many apologies to everyone if I've gotten anything wrong!

那附近有没有邮局？ = Is there a post office around there? (near there) 那 refers to something already spoken about. 那附近 = around there 这附近 = around here 有没有 = is there...? This is a very standard question. When answering 有没有 questions there are 2 possibilities: 1. 有 = Yes, there is. 2. 没有 = No, there isn't.

Your example is the state of 1-⑴-③ 1. the direction of 那： ⑴那：as a demonstrative pron. ① It indicates person or thing that is distant in space or time from another 那+(number & measure word)+noun. ex.那个人(that person) ，那两棵树(those two trees) Sometimes那 can be put alone in front of the noun. ex.那时候(that moment)=那个时候，那地方(that place)= 那个地方 ②那 can be used alone as the subject of a sentence. ex.那是谁(Who is that?) ex.那是我们的老师(That is our teacher.) ③那+locality words(indicating position or time) ex.在那上面(above that )，在那里面 (in that)，在那外面(out of that)，在那周围(about that)，在那附近(about that)，在那下面 (under that ), 在那之前(before that )，在那以后(after that) and so on. ⑵那：as a conj.= then/well then It is followed by a sentence. ex.他病了，那我去吧。（He is sick, then let me go.） ex.天太冷了! 那多穿点。(It is so cold. Well then, put on more clothes.) ⑶some common words about那： 那儿=那里=那边(there)，那些(those)，那会儿(in that moment) 那么=那样(well then or so/such)，ex.她的脸那么红(Her face is so red.), 你帮了我那么多(You help me so much), 他是那么好的一个人(He is such a nice guy.) 2.有没有：it is the affirmative-negative question form of the 有sentence. The translation is just like “General question” in English, =.Is there …? or Are there…? or Do/does someone have ….? Note that the answer is an affirmative (有)or a negative（没有）. ex. 那里面有没有书店？（Is there some bookstore inside?） ex. 你有没有问题？(Do you have any question?)

有没有 = positive answer (有) + negative answer （没有）such form usually used in interrogative sentence. basically u will have 3 answers: 1. 有 2. 没有 3. 我不清楚（我不知道） PA+NA usually are: verb+verb e.g. 来不来 ： 今天晚上的晚会你来不来？ 看不看 ： 明天有场电影你看不看？ adj+adj e.g. 漂亮不漂亮 ： 我今天穿的上衣漂亮不漂亮？

yep, i agree with 牛肉面. 有没有=is there……？ 那=there （refers to a place ) that's the most common situation. sometimes, depending on the context, 那 can mean "well", "so" etc... like, "well/so, is there a post office?"