Hi @Daniel Flesher it depends a lot on how hard it is to secure permits in Philly or where you choose to do this and how good you are at guessing what a developer wants to build.
In the SF bay area you don't even need to secure the building permit just having planning/zoning approval (entitlements) can add a huge amount of value to the land because of how long it can take to get these approvals. If you take it to the next step and get the building permit as an architect that actually opens you up to a lot more liability because it is your life safety and waterproofing details now on the plans. Not sure about the litigation rules in PA but in CA not entity can protect you from these. you are on the hook for construction defect litigation for 10+ years or whatever your state's statute of limitations.
I would take a look at what Jonathan Segal FAIA has done in San Diego. He goes all the way through construction and holds his buildings as long as possible and only sells after the litigation period is over. If you do it right it is like BRRRR on steroids. He has a study at home program. It is good for inspiration but not great on concrete steps. One thing I learned from him it is much better to get paid rent from your building than architecture fees based on tax treatment and depreciation offsetting the income but that was prior to the new tax bill so that may have changed a little.
I would also check out this podcast Chris Porto is taking projects through entitlements in Oakland then selling them. He started by doing rehab flips https://itunes.apple.com/us/podcast/smart-growth-d...
as far as carrying costs and closing costs that may be mitigated by doing an options contract but you need to make sure you have enough time to get all the way through the level of permitting you want or a way to extend the contract.
