I use the RESPtracker app.

I also know that Baselane is continuing to evolve their app.

If you are looking at Property Values, use zillow.com, that is what we use to fact check properties values. 

I do it myself and takes 20 to 30 minutes a month (did it yesterday for Dec), with about 7 of those minutes for 1 property in Blount County, TN which requires the form to be manually filled out, write a check, address an envelope, scan doc and check for my records and walk it to my mailbox.

At least, until I can find another app.

@Jeff Landers Kindly check my message.

I’m not sure if it has a pay bill feature, or checks.

Quote from @Ogonna Odo:  Small ones will not, they typically like cash or checks.

After they book, it's still a good idea to use the platform app for communication because then the platform has a record of what you and the guest have said, in case you need it when a guest does damage and admits it to you, but later denies it to the platform.  

You can setup a "guest mode" allowing the guest to enter their check-out date.