I'd suggest meeting with a lender now for 2 reasons.  1) You may be ready to go sooner than you thought.2) If you are not quite ready yet, they may be able to point out other things that you can work on along side of improving your credit.  

So it tough to nogotiate when they walk or improve product quality when there is no problem.   

I try to improve something every vacancy.  

Over the years I have had agents say they will do all the steps to succeed only to be full of hot air after 1 week.

They are salespeople and are usually full of hot air.  

I know for sure once you alert them they may want to come in and do walk through of the entire property to see what kind of improvements were made over the years that weren't taken into consideration.

The opportunity to sell and improve the quality of my portfolio had begun to outweigh the option of holding any longer.

Ideally we'd like the investor to get his money back + interest in 3-6 months and be able to leverage any tax breaks from the depreciation and repair (not improvements) BUT we don't want him to have his name on the deed or anything.  

Make sure you're improving your financial position now though. 

For example, if it increases cash flow enough to pay for itself over 5 years, and the market CAP is 10%, it will, by definition, increase the value of the property (from a strictly income approach appraisal perspective) by double the cost of the improvement.