Good morning, I too was in a similar situation with a very mixed fleet like yours. I found Fleet Maintenance Pro ( https://www.mtcproweb.com ) and have been happy with it so far. It tracks mileage/hours, daily inspections, inventory, scheduled maintenance and alot more. It has probably more features than I could even imagine. If I recall its about $95 a month and less per month if you pay annually. I found thier customer service is top notch, american based and it seems like I always get the same person to help me. They do offer a one month trial period wiithout having to do too much to get the trial going. When I was looking for options after my last provider dissapeared (LONG story that I care to forget lol) I found that many of the providers do a very hard sell on their product, not so with this one, pretty much try it out and call if you have questions I've been using it for 2 years or so now and have been very happy with it. If you have any specific questions feel free to PM me or ask them here for the group