Rehab Question

[Ravi Patel]

Hey all,

Apologies if this is the wrong forum section to ask this. Did not really see where else it could go. 

So I have a great home in Fishtown, Philadelphia, PA area. It's a 2 bed 1 bath. It's a bit small at 700 sq ft. We are thinking about extending our home into the backyard region. We have a 10x10 backyard, and were thinking leave about 3-4 ft in the back for just putting HVAC system and such. Our contractor (who is licensed) said he can definitely extend it. However, he said getting permits for in Philadelphia would be like 2 months. I wanted to see if anyone has ever had experience of doing something without permits ? He is strongly advocating that we just not get the permit and extend it. However, I am worried that when we try to sell the place we may run into trouble. 

We are planning on making the master bedroom upstairs bigger and include a master bath, along with extending the other smaller room upstairs. Then we will build a 10x10 room downstairs as well so turn it into a 3bed, 2bath place and add about 250 sq ft of space total. 

All comments appreciated. Our realtor said he does things by the books, and is against not getting permits. Contractor said he can get it done in 3 weeks if we don't get permits.