It is obligatory for a person who does not have either the sacrifice or it’s money, to perform ten days of fasting, three days sequentially in the days of Hajj (seventh and eighth and ninth of Dhu’l-Hijjah) and seven days after returning home. If he/she could not perform fasting in the seventh day, he/she should do that in the eighth and ninth days after each other and one day after the thirteenth day, and these three days should be in the month of Dhu’l-Hijjah (and being in travel in not a obstacle for performing fasting in this condition), but he/she can perform other seven days in other months, sequentially or separated.
Whenever a person perform Umrah al-Tamattu’ and comes out of Ihram and wants to abstain from doing the rituals of Hajj, he/she has performed no sin if this is because of illness or another obstacle, and if it is the first year of his/her ability of Hajj, it is clear that he/she has not been able of performing Hajj, and if Hajj has been obligated for him/her before then he/she should perform Hajj al-Tamattu’ completely in the next year.
But if the pilgrim abstain from performing Hajj without any excuse then he/she has performed a sin (if has is obligatory or Mustahab) and there is nothing else on him/her and should perform the obligatory Hajj in the next year and it is obligatory to perform Tawaf of Nisa’ and its prayer any way.
Killing a bee and other insects like a fly or mosquito is not permitted in the state of Ihram (as obligatory precaution) and if the pilgrim kills that insect deliberately, then he/she should pay the atonement which is some food (for example one loaf of bread to a poor person) but it these insects causes him/her harm or disturbance then killing them is permitted and has no atonement.
It is obligatory for a person who performs Umrah al-Tamattu’ to stay in Mecca and complete the rituals of Hajj (if Hajj is Mustahab or obligatory) and he/she can go out of Mecca only if he/she is sure than he/she can return and perform Hajj. Therefore going to close places like the cave of Hira and like that, which do not cause trouble in performing Hajj, has no problem.
Also servants of caravans and others can go to Jeddah, Medina or other places for performing necessary tasks, on condition that they are sure that they can return on time for performing the rituals of Hajj. And it is an obligatory precaution for them to become Muhrim to Ihram of Hajj when they want to leave and remain Muhrim until performing the acts of Hajj; but if this act causes severe hardness then they can leave without Ihram.
Whenever a person goes out of Mecca for performing a task after completion of Umrah, Ihram is not obligatory for him/her if he/she returns in the same month (for example the pilgrim performs Umrah al-Tamattu’ in the beginning of Dhu’l-Qa’dah and depart Mecca for Jeddah or other places and return in the same month of Dhu’l-Qa’dah), but he/she should become Muhrim if he/she returns in the next month and performs Umrah again and this will be considered as his/her Umrah al-Tamattu’ and it is precaution to perform a Tawaf of Nisa’ and its prayer for the previous Umrah.
Being in a roofed vehicle in the city of Mecca in the state of Ihram has no problem (in day or night) but it is better to observe the precaution in the place that is out of Haram (that side which is beyond Masjid al-Tan’eem).