They've expressed much interest in buying the house, since I brought the topic up.However, I have *no* idea what I need to do, to do sell a house, I've never done this before!! 

He seems to be a big boy with no problem expressing himself.

My tenants have occupied my CO rental home for many years now, and over the years, they've repeatedly expressed interest in purchasing my property.

I would recommend RE Express or CA prep agent schools, they have FB groups to help with studying and things of that nature as well!

I got started doing just one sizable assignment deal and through that process it caught the attention of one of my friends who expressed interest and eventually became my investing partner.

He has expressed an interest in selling some of his rental properties because of his age.

I’m closing on a 4-plex in two weeks and the seller has expressed interest in selling several other multis that he owns.

It sounds like you are  underestimating the value of having cash working for you and there's a lot of potential for making money on leverage right now with super low interest rates.Stock markets are returning historically on average 8%/year in indexes, there's dividend stocks that can be 5% yield etc. so it is a bad idea to spend all your cash buying properties outright when you could borrow money at a lower % rate and give yourself the freedom to invest your cash into building more wealth.There's an expression that rich people get rich by using other people's money - in this case the bank's at low rates.

Equity Passive Income.15. iBuyer Option through Express Offers - Create Multiple Offers for your sellers.16.

ExpensiveMany hard money lenders are set up for the express purpose of financing acquisition/rehab projects, which can be of benefit.What do you recommend as far as financing an investment?