"I plan very carefully to be sure my lease renews in the summer time."
You are correct in your plan. It is all the more reason not to allow your tenants to dally. Either they sign or move out. There is no middle ground. Again, make it clear that there will not be any new upgrades or remodeling during the next lease term. The rental is being offered as it is now. Here is what you need to keep in the back of your mind. Renters are just another class of homeless. Homeless people do not get to dictate how landlords spend their money. You are in the diver's seat. Push on.