If you must be the on-the-spot final decision maker and are also the sort of person that can be talked out of $1200 per year without giving yourself time to think through your options or come here for advice then please hire a manager.No request, no matter how small it seems gets an instant response!!!

A lot of options and it depends on your goals.

Another option I thought of was getting an Auto equity loan on my 2018 Ford Fusion.

One good option is being a local airbnb cohost for a property near you.

He does not need my money in that he has other options. 

Is an ADU (accessory dwelling unit) in option for your home?

Most though will have a due date in the beginning of the year such that you have the option of paying it in the prior year.

Probably your best option will be to make some improvements, (maybe not the full $450k but enough to make it sell for as close to top dollar as possible without over-spending on improvements), and your 2nd best option is to sell it "as-is" for an appropriate price given the current condition.

By simply making the requirement to make vacant for closing alone with typical "time of the essence" language the buyer has the option to walk away if the seller hasn't met their obligation but can also hold the seller to the contract or work the deal further.

These are the options I've thought of:a.