Assuming you derive your monthly income from investing cash flow is necessary where as appreciation is simply a bonus for having invested in a smart income producing property.The strangest thing about most appreciation investors is that they usually never realise their gains since they are reluctant to ever sell and can not pull out cash due to the further negative impact on cash flow.

A return of 10% or better should be easy to achieve in the right market plus any appreciation as a additional bonus.

They would bonus him just to take the loan application, regardless of if it had any chance of closing or not.

Again, not my cup of tee personally, but if you want it as a wealth preservation hedge, I think there are better ways.If the SHTF really, then I'd rather have guns & ammo, canned food, a water purifier, farmland, and fish hooks before I'd want to own gold ... and these things are all less costly than gold as an added bonus.

You can get it here in your Pro bonuses https://www.biggerpockets.com/promotions

Do they get a percentage or bonus for each apartment rented?  

As an added bonus, we would love to speed up the process of getting someone (possibly us) into that house, as it is not helping the property values of the surrounding homes.

They would sell their house and have some bonus money a few months later.

Any other bonuses like bookkeeping or quick books training is a plus but not required.

We also got closing costs covered which I can't help but think was partly the sellers agent trying to push through the deal to get that extra bonus.