Newbie looking at house to buy and flip with open permits

[Marion Weerasuriya]

Hi I am considering buying a single-family home to remodel and flip but in the description it says "buyer must assume open permits."   Also the property tax assessment for 2017 was $20,000+ based on a value of $940,000 and the listing price on the property right now is only $499,000.  What does it mean that the buyer must assume the open permits and what are the possible pitfalls of that? Also if I buy the house for around $400,000 will the tax assessor revalue the property and charge property taxes based on what I've paid? Thanks for all of your help I am new to all of this but very excited to dig in and get started!! I  appreciate all of your expertise! Marion 😊