Based on manufactures guidelines:
Based on solar insolation and overall production we aim for 10 years depending on the system.
As long as you have batteries and or a backup generator you will not lose power.
Yes, we can take care of that for you. The price for our clients that have bought their system through us is around $2,000(for a 28 panel and under system) to take them off and put them back on. If the system was installed by another company, we would have to quote it out individually.