Once 80% of the building was sold, the taxes were adjusted - and tripled from the original rate!

Triple check their profitability numbers.See if you can find out why they are selling a profitable property. 

I'm paying more than triple that but then, he has 50 staff, is leap and bounds ahead of where I am and you don't get a free handout from anyone at that level (I wouldn't expect one anyway!) 

It's YOUR project, YOUR business, YOUR house -- which means when something like this goes wrong, it's YOUR fault.Given your description of the issue, I'm going to guess that this guy is a handyman type, and isn't full-time tile contractor -- professional tile contractors wouldn't make a mistake like this (they would check, double-check and triple-check their work before proceeding).  

Sure, some will triple/quadruple their earned income, and can invest more aggressively in their 40s, but more likely, the majority will triple or quadruple their family size instead (going from being single, to having a spouse and two kids, on the same earned income...ouch!)

A Triple-A rated bond earns you 2-4%, but there is little risk of default.

Keep your eyes open and double check even triple check your numbers and don't be greedy.

I was able to get into a triple decker with a decent amount down. 

But the second you invest YOUR mone, believe me suddenly you triple check all the numbers!

You'll be lucky if it's only double that and probably closer to triple.