You are therefore afforded a bit of stability.Your ability to raise the rent is based on the lease.  

I'm with you, windowless envelopes are the way to go.Windowed envelopes have the connotation of being a bill, credit card offer, or spam mail and we do not want our letters to scream "SPAM!!"

Rehab them and keep them full of the bad element?

Where as an apartment if a tenant moves out, it will not have an impact on you having the ability to make the mortgage payment.

I don' have the ability to predict like the Magic 8 Ball (remember those?)

I've never had good luck working with a significant other in the same job, but again, that's me not you.RE is amazing and I see myself eventually becoming full time as well, but for the moment I love my corporate work and it is what funds my ability to be an investor. 

"If Buyer has an ownership interest in more than X units in the community, during the term of the loan Buyer agrees to rebate half of the rents received for all units to Seller as compensation for Seller's increased risk that Buyer's finances may change as a result of HOA actions and may lessen Buyer's ability to repay this loan."

Then I would suggest putting in an offer with an inspection contingency to allow you time to visit the site/area personally, but giving yourself the ability to back out if you aren't comfortable.

He feels like he would like to have the ability to look for the best paying job he can get and not be forced into possibly having to take an entry level position just to stay in the same field.

As @Kevin Hunter mentioned, try to do everything - the only thing stopping you from perusing both at the time is your ability to be efficient with your time and prioritize.