I am going to put my town house soon on the market in the suburb of Washington DC. Question I have is about roof age and AC and if I should change it or sell as is? Roof is fine and AC works and not damaged but they ...

@Chip Marchandin order of most real estate-y to FI to general business:Buy, Rehab, Rent, Refinance, Repeat by David Greene (RE)Real Estate Investing Gone Bad by Phil Pustejovsky (RE)Investing in Real Estate by Gary Eldred (RE)Quit Like a Millionaire by Kristy Shen (FI)Playing with FIRE by Scott Rieckens (FI)I Will Teach You to be Rich by Ramit Sethi (FI)The One Thing by Gary KellerAm I Being Too Subtle by Sam ZellShoe Dog by Phil KnightThe Big Short by Michael Lewis

But as I am getting older and families start being built, my lifestyle choices make it hard to participate in family activities because of the dark side of the restaurant industry, "Work while others play".

I always play conservative in case the bogey monster down turn happens. 

Thank you Marcello great input was wondering what was the leverage means other investors were employing the heloc option versus cahs out refi , although heloc allows one to be your own bank ready with cash to strike when have found potential good rentals, but then we have to weigh in the possibility of rate hike which will be expected eventually with a draw period of 10 years and then have to pay P/I amortized payment with variable rate for next 20 years, so what is the typical play then after 10 years, does one payoff the balance as an investor and get a new heloc since some equity got built by more principal pay down and possible market appreciation or can one get a sizable amount from their heloc they have on a primary home that still draw period available and is interest only and payoff on the heloc on the VAcation home.   

Assuming the land cost was affordable and clear, what major financial challenges can come into the picture upon the decision to develop a small complex and is there a "play" these days for developing smaller complexes (30-40 units)?

I’m slow playing it, and building rapport, I just want to have my mind right when it comes to the negotiating.

Looks like a great long term play @Eric Prine!

It’s one of the few real estate “investments” you can allow your emotions to play a roll. 

If you're buying property for the long term play you'll get a 30 year conventional most likely.