I can't get the utilities arranged, nor an electrician lined up to fix some issues ... without knowing the move in date.Suggestions??

If you closed an account and therefore changed the payment arrangement without proper notice to the tenant here, CA judges would be all over that. 

If there is anyone else interested, please respond to this post and we can arrange a time to meet.

There are many reasons to use a servicer or payment service, such as an owner moving and leasing a property, while a new payment arrangement is a red flag of sorts it doesn't send up rockets of red flares.

Are there flaws or pitfalls I need to think about prior to arranging this?

You might be able to arrange something with a friend or family member.

At this scale, you need legal assistance, this can be done with a master lease arrangement and you can also secure your interest as a future advanced note/obligation agreement to cover additional money invested on repairs.

Certainly, arranging for tenants to pay utilities would be a big plus (but the rents might need lowering a bit at the same time)?

If you don't have the cash, find a partner and arrange a split. 

Is there a way to arrange a private deal with the retiree and pay him back directly over time if he agrees?