It depends on how you came to stay the summer.
If you were invited to stay, then "having me stay" is correct.
If you asked to stay, and they permitted it, then "letting me stay" is what you should use.
Wishes are unrealizable conditionals, so we backshift the tense of the verb. can is backshifted to could, will to would, and present simple meet is backshifted to simple past met. be is an exception because it has a proper subjunctive: am/are/is backshift to were.
You mention guidelines about action words for future actions, but the word now in examples a and b locates the sentences in the present, so these guidelines don't apply. Furthermore, these guidelines explain what you should do, but they don't explain why you should do it.
I believe that it is much more effective to go back to first principles and make a complete sentence that expresses exactly your wish as it can happen or is/will be happening, then backshift:
I am eating that cheesecake
I wish I were eating that cheesecake.
I can eat that cheesecake
I wish I could eat that cheesecake
My father will let me borrow the car
I wish my father would let me borrow the car
Note that eat is an action word, but the first two examples relate to the present so the "action verb" rule doesn't apply. The first example does not require could and the second example does. Working this way, you can see why could is necessary- because can expresses ability / permission, and can -> could. The third example is about a future event, so will -> would.
You are right that a) and c) are correct. To find out what's wrong with b) and d), remove the backshifts and see what you get:
b) I meet her now.
d) I meet her more often.
b) doesn't make sense because meet is present simple, and we don't use present simple for current events- we use present continuous. To find the correct way of talking about now, change that sentence to present continuous and backshift it:
b) I am meeting her now
b) I wish I were meeting her now.
d) doesn't make sense because more often requires some reference level. If you talk about capability, there is an impled reference level:
d) I can see her more often [than I do]
d) I wish I could see her more often [than I do]
Best Answer
is a hope that hosts typically express when guests/clients arrive. It's what you expect to hear from a receptionist when you check into a hotel. It looks ahead.
When the guests come to settle the bill at the end of their stay, the receptionist may well say:
This looks back on the period when the guests were staying at the hotel.
It's wrong to say:
because it confuses the future and the past - and it's not idiomatic.
It's possible to write:
but it's never idiomatic to write:
Instead, you would say: