I personally use 20% for the type of houses you describe above.In addition, while maintenance costs usually cover routine items, you should probably consider accounting for capital expenditures as well i.e.

Finally, if there is not sufficient credit history and/or you are uncomfortable with the resources presented, ask for a guarantor.

Rob,I do this routinely.

I am uncomfortable because I have no recourse against anyone who owned the property before this previous seller.

I'm just going to proceed with the normal routine and hope for the best...

But it's awkwardly uncomfortable (and maybe even painful) to watch it happen sometimes..

It had barked snarled and backed up away from me routinely for weeks.

Not really sure what your question is, however if the issue is that you are uncomfortable with determining value, since it's just one property, you could search online for an appraiser and spend a few bucks to let you sleep better.If there's access problem, you can order a drive-by appraisal for $200-300.

Basically, the same routine a bank does, YOU buy it, THEY get a mortgage on the property.

It is rarely physical labor but most often it includes driving neighborhoods, looking up ownership records, making uncomfortable calls, etc.