Get to the point where you have an intuitive idea for what deals look good, so that you can pass on the 99% of mediocre/crappy ones, and only investigate the attractive few.You need to learn to value deals better than the realtors, because their incentive is to complete a transaction and move on, unless you have a demonstrated capacity to do several deals in the near future.

Although SFH doe attract better tenants you just have to be specific in filtering your tenants.

I obviously would rather have the tenants pay but, would that make my rental less attractive?

The only thing really attractive about it is the owner financing..

This will extend the life of the floor and will give an apartment a fresh look that will attract tenants.

Doesn't sound all that attractive, but at least you haven't burned a bringe or ruined your name by bailing on a deal - which is really important for investors3.

But, from a cash-flow standpoint they look a lot more attractive than Denver-area properties.  

I also looked into multi-units (duplex,triplex etc), but they all look run down or unattractive and the last thing I want to to attract the bad tenants.I guess my questions are: Are single family homes and condos good investment options or should I stick with apartments/multi units?

It's truly a nice ski property in New Mexico, but according to the listing agent, land is not moving in that market so even lowering my price substantially below my costs won't attract any offers.  

Newer homes tend to attract a better quality tenant.