@Angela Persico based on what you've told us, I think that your top priority should be to have this tenant leave ASAP and find a new, better tenant. The longer you allow this tenant to stay and keep missing payments, the worse the situation will become (and the more money you will lose).
There are a variety of ways to get rid of a tenant (eviction is one, but it's time consuming and can cost a lot, and you need to follow the law and local regulations). Cash for keys may be a better option (pay the tenant to leave).
I'm not sure hiring a property manager will solve your issues...Good PMs are very, very rare (and often, good PMs have no interest in taking on a single house with a deadbeat tenant and a distressed owner--they have bigger, better fish to fry). Moreover, finding, screening, and managing a PM (yes, you need to manage your manager) is challenging, and it often requires experience as a landlord/PM (an experienced landlord/PM is better able to screen PMs, find a competent PM, and manage that PM)...but, you are not an experienced landlord/PM, and it by your own admission, you're pretty bad at it...so, you're ill-equipped to find a good PM and manage them through a solution to your challenging problem.... We all hear horror stories of inexperienced landlords hiring inexperienced and incompetent PMs, and it costing the LL a ton of time, money and frustration--in your situation, a PM is almost as likely to ADD to your problems as they are to solve your problems. ...not to mention the fact that if you did get a PM, you'd be immediately handing a them a big problem to solve (a problem you created), and most PMs do not have the experience, or the incentive to solve such a big problem for a brand new client that they have no history with, who only owns one property. If I were a PM, why would I want to put in the serious effort, and expose myself to potentially serious liability, to solve this giant problem you created, when I'm barely making any money in the process and it's clear that you would be a small time, high-maintenance client? PMs want big time clients with large portfolios, and they want those portfolios and the tenants to be as low-maintenance as possible, and they want the LL to be as low-maintenance as possible (you're literally the polar opposite of all that, based on your story). To a PM, you will be viewed as low profit, high maintenance, and high liability, and it's very unlikely they will have sufficient incentive to solve this problem for you (even if they have the experience to solve it--which they may not).
Even if you could magically find a PM who is experienced enough, and motivated enough to solve your problem for you, you need to take responsibility for this situation, take a role in solving this problem, and learn from it so that it never happens again. If you plan to keep investing in real estate and continue being a landlord, then you need to quickly improve your approach to avoid these types of problems, and having someone else (like a PM) solve your problems for you doesn't make you a better landlord...if you don't take responsibility for this situation and learn how to solve it, and learn how to avoid it in the future, then this type of problem will re-occur (even if you do have a great PM--because again, you need to manage the PM, and if you're not a competent LL, then your management of the PM will also be incompetent). The PM is NOT a magic-bullet solution, because if the owner is an incompetent landlord, then they will be incompetent at managing their PM, and as a result, the PM will be ineffective at solving tough problems.
How do you become a competent LL? There are countless books, podcasts, forum posts, youtube vids, articles, etc. to learn from--obviously, BP is an excellent source for much of this info. Read up, and try to learn from other people's mistakes as much as possible.
How do you fix this problem with your tenant? I think the first step is to approach the tenant and say "Look; this clearly isn't working out. You need to move to a place that better fits your needs. How soon can you move out, and what do you need in order to move out?" and see what they say, and then work toward some agreement for them to leave that works for you....If they DON'T agree to leave, it's probably time to begin the eviction process. If they DO agree to leave, write up a new contract that cancels the existing lease, and stipulates the exact terms of when and how they will leave, and what financial transactions will occur. This new contract also needs to explicitly describe what will happen if they don't abide by the contract's terms--for instance, what will happen if they don't leave the property in good condition by the agreed upon date, or don't pay you the agreed upon fees by the agreed upon dates? ...this contract also needs to include agreed upon terms for payment (will they pay you their outstanding debts, and if so, when and how will they pay? will they be liable for late fees? are you waiving some or all of their outstanding debts to incentivize them to leave? what is the status of their deposit?, etc.)
To quote one of the greatest movies ever, you need to "make 'em an offer they can't refuse" and incentivize them to vacate and abide by the new terms you put in your new contract. You could incentivize them to leave and abide by the new contract in many ways. For instance, you could agree to cancel some of their outstanding debts, and/or you could make it clear that their security deposit will be withheld if they don't leave under your terms, and/or make it clear you will file a lawsuit to recover the money they owe you if they don't meet your conditions, and/or get a collection agency involved, and/or you can make it clear there will be an eviction for non-compliance with the contract (among many other methods)...I would also suggest reading up on cash for keys, and seeing whether that strategy could work...talk to the tenant to get an understanding of why they are staying, what things would prevent them from leaving, what things would incentivize them to leave, etc. ...ultimately, you need to create a new agreement (in a new contract), where the option of leaving and abiding by the terms of your new contract is MUCH more appealing to the tenant than the option of staying and/or violating the terms of your new contract. However, before you pursue ANY of these options, you need to educate yourself on the relevant laws/regulations to make sure you're not doing anything illegal--a decent lawyer can help you understand which of the various options is feasible and lawful, and can help you create a new contract for the tenant to sign that stipulates the terms and conditions for them to vacate and (if relevant) re-pay their debts.
At the end of the day, you need to assess what types of lawful incentives you're willing to create to get this tenant out ASAP, while also doing a cost/benefit analysis of how much money and time you're losing in the deal, and how much money/time you can save by getting a better tenant... and no more payments via checks! (we have much more effective payment methods these days).
Good luck out there!