Unless this is peculiar to PA laws, an ejectment is usually a term reserved for special situation related to possession that don't fit the category of an unlawful detainer. 

Start opening the cases that are called Unlawful Detainer (or whatever your state calls it when a landlord takes a tenant to court) and see what attorneys are representing landlords.

If you were to give notice tomorrow, the 30 day period would run through May 19 and the lease would expire at the end of May and they'd be required to vacate by then.If the tenants do not vacate at that time, they are then holding over illegally with no right to remain there and you can file a forcible entry and detainer action (eviction) in the municipal court.

At that point if they haven't voluntarily vacated, your Attorney will file an "Unlawful Detainer".  

First the Park will probably serve a NOTICE TO QUIT, for MHP this is 5 days.Then they will file FED Forcable Entry and Detainer.

While Aaron is correct that if you terminate a MTM tenancy and the tenant refuses to move you still have to go through with an eviction (unlawful detainer) to recover possession of the property, here's the big difference between a MTM tenancy and a tenant on a year-long lease right now...Let's say you have a tenant 6 months into a year long lease who stops paying rent. 

You can represent yourself (in pro per) without being licensed, but not someone else.Here's a few links on the topic: https://nathanmubasher.wordpress.com/2017/02/20/a-corporation-cannot-represent-itself-in-court-in-california/https://www.avvo.com/legal-answers/does-an-llc-need-to-be-represented-in-an-unlawful--367580.htmlhttps://kaass.com/california-corporations-facing-lawsuit-must-be-represented-by-an-attorney/https://www.occourts.org/self-help/landlordtenant/preparingyourcomplaint.html (this one is specifically about filing Unlawful Detainer complaints and says "If the plaintiff is a corporation, they must be represented by an attorney.")

She may be "unlawfully detaining" on your property if her lease has expired, hasn't been paying rent, and/or you have filed for an eviction and the judge upheld your claim.It's a tough situation no doubt, but not a crisis.

Each state is a little different, but it shouldn't be hard to find the court or courts in your area that handle evictions (unlawful detainers).

.-- If you do not follow the terms of the “Notice to Pay Rent or Quit” we may then begin eviction proceedings against you and you will be charged with the crime of “Unlawful Detainer” if a judge upholds our claim.The amount of rent now due, as of today’s date _________________, is as follows:Current Month Late Fee_______________Current Month Rent_______________TOTAL DUE_______________Time is of the essence.If you have not already posted your rent via the mail, please call us immediately to make arrangements for us to collect the rent in person.Thank you for your prompt attention to this matter!