and ability to execute ..  

In my opinion the bubble has already burst in Manayunk and while home values will likely continue to rise, it won't be anything like the explosive appreciation growth of the last decade. 

Congrats on the successful Flip and ability to pivot your strategy mid-stream! 

Providence and surrounding neighborhoods don't have positive inflation-adjusted growth over the long-term (shocking) so to make money in this city you need to i) invest cyclically and ii) have access to good deal flow.

To answer your other question, yes, going bigger will accelerate your growth as an investor.

If you sold it on land contract then that person has the ability to get the homestead deduction which would lower the taxes. 

*For further details, you can find specific calculations in the source of the spreadsheet shared above.InquiriesI am compiling additional data to continue my research on favorable rental markets including wage information, job growth, home prices, rental prices, etc...

Furthermore due to the potential target group and vacating I think it will be good the city has a university for future growth and appreciation of the city.

Underwrite off historical and not the last 5 years for rent and expense growth as the last 5-8 years are a bit flawed and are unlikely to hold through the life of your project.

I used to be obsessed with spreadsheets and counting very penny I saved for the month, until I realized it was hindering my growth.