Bristol Borough Permit and Inherited Tenant Questions ASAP

[Harold Arnold]

Newbie in need of some timely advice. I just purchased a Triplex in Bristol Borough (two units in main house; one detached unit in rear). Main house is 100 years old. Inherited tenant in 2BR/1BA first floor unit whose inherited lease goes until Sept 2017. She's lived there 11 years and wants to stay. But, from my valuation she is well under market rent (paying $750 for unit and access to large basement area vs. what I believe is ~$900 market rent). Question #1: Would you honor her existing lease through September? If so, do I still have her fill out my own lease at her existing rent or just leave her old lease in place until it expires? 

Second question, Inspection revealed knob and tube wiring on second floor unit. I've had paneling taken down to start rehab. Unit mostly needs drywall plus I want to install stackable W/D in unit which will require a plumbing run and rewiring all electrical to get rid of knob and tube. Would you go through Borough permitting process for all of this work or just have contractor get started? Contractor is ready to start but I'm feeling uncomfortable proceeding without a permit. What would you do?

Thank you in advance for your wisdom.