If you're mortgage is lower because you were able to get the house at the right price, with the right terms, that 50% for expenses wont seem so daunting. 

Eventually you wont need it and you will be able to come up with more accurate repair numbers.  

I don't want to scare my tenants away but also want to keep the building from being destroyed.

If you try to grow too fast without enough money, experience or connections, your foundation will crack, and you wont have any money to repair it.

I've seen insurance companies have exclusions for that on aggressive breed dogs, so check that out first.Here are the pros and cons in my experience:Pros:- tenants seem to stay longer because its hard for them to find places that will take dogs- I charge a $500 per dog additional security deposit & $25 per month in pet rentCons:- I've had dogs completely destroy yards, and it takes weeks and even months to get the grass to grow back (interestingly enough, this is not an issue for new tenants who have dogs though since there dog will likely do the same)- scratches on doors and chewed carpet- Neighbor complaints about barking (Haven't had this much at all)I have 14 units and I do allow dogs in all of them and have not had any horror stories yet, at least none that resulted in a lot of out of pocket expenses that the deposits did not cover.

I would raise her rent to $1900 and see what she says.For me if she walked I would not care because a husky and three teen boys will destroy your property.

In Maryland you wont make much doing rentals (Other markets you can like NYC and Boston) and you have a high liability with rentals.

I wont claim to be a master pricer.

I guess the danger is that if you price to high, not only will you not get buyers, but banks wont appraise.

I do know that there is a 6 month seasoning period for traditional banks.I have tried with few small banks and mortgage companies and got burnt with multiple credit pulls and non attentive bankers taking 30 days to come back and tell me they wont do loans for investment properties (even after I had clearly mentioned it in the application).