Answer:
Turn off her phone until she is on a break.
Step-by-step explanation:
This would be the simplest and most effective way for Lainey to look for a new apartment without worry of outside factors. Telling her realtor she can only receive messages will still make Lainey read and then respond back to them, taking up more time than a phone call would. Limiting the time is not the issue anymore as in the excerpt, the few minutes she spends on each call "are really starting to add up." The last one just doesn't make much sense at all. The issue is time, not customers seeing Lainey answer the phone.