I'm looking to build 2 sets of one story townhouses with 5 units each so 10 units total, 2BR/2Bath. 

for me got my RE license at 18 and hit the streets.. tough first 6 months.. but that first commish check of 900.00  when at the time  75  a great job paid 8 to 10 bucks and hour.. and it took me I calculated about 6 hours total time..

I've heard that you can make them custom online and save a bunch. 

Estimates to make the property rental-ready now stand at $8,000, meaning a total loss of about $13,000 in five months.

There is valuable information, however it is all available for free online with YouTube and google.

." - TOTALLY NOT TRUE

Specifically 1) what is the total market share available (especially since you want to stay in that market not grow into others) 2) who makes up how much of that market share? 

I liked Nathan's reply because it is totally possible to buy rentals with little to no money down, but you should definitely have some sort of cash on hand for general operations and unforeseen events. 

Spending 15 seconds online and I see that older homes sell for about $100K less.

@Angel Alicea - You would need $29k down total and you are good to go regarding loan size.