Have a process server physically give the notice of non renewal. and as Teresa said, try calling from a different number

If you are a business, 3 backup is best. 1 Local (in your business environment, like a back up server.), 1 stored in a cloud environment (and secured) and 1 off site.

The website 51west.properties also scores low on scam advisor ("owner is using a service to hide their identity, high number of suspicious websites on the server, registrar has a high % of spammers and fraud sites, website is (very) young, website appears to be hosted by a company with a bad reputation", all according to https://www.scamadviser.com/check-website/51west.properties...)Trust your instincts. 

Can I risk building a home at the slot and sell it which will be faster than selling a lot? 

Please provide a fewtime slots for next week so we can coordinate sending someone to checkboth apartments at a time when the tenants are available.To help me better understand and to better identify the source of theleak, please provide a picture of your bathroom showing where the leakis located, such as above the toilet, bathtub, or another area.we’ve noticed that you’ve asked in almost every email, both now and inthe past to let you know when your ceiling will be repaired.

Do you serve notice immediately on July 1st yourself, do you hire a Server/Attorney?        

We received this letter from Toledo LMHA Lucas County's Section 8 administrator.I don't know if they had a data breach and a bunch of landlord and client personal information was stolen or if they lost their server and backups.

(We switched to commercial financing when we ran out of loan slots with Fannie Mae.)  

It's only been a week, but what are my options if they do not return and the RV just sits in the slot? 

But one can buy a pearl every now and again I suppose kind of like playing the slots looking for that 100k payout :)