Deal Analysis Help

[Jason V.]

So I'm not a flipper - my wife and I focus on long term buy and hold, typically looking for distressed properties to rehab, which gives us a better deal as well as some equity in the property. 

But a SFR came across my radar, and while it wouldn't be a great rental (although it wouldn't be a bad one) I'm looking at it from the perspective of a flip.

Asking Price: $35k

Taxes: $3300/year

2000 sq. ft. raised ranch - would be a 4 bed, 2 bath when done.

Sits on a wooded acre in the country - all the neighboring houses are very nice

Rehab - Fairly light to moderate. House was built new in 1996, siding and windows look good. Roof could go a couple more, but I would put a steel roof on (not visible from the ground, and very common around here. Cheaper and lasts 50 years when shingles only last 15. ~$5k) Needs every wall painted and every floor re-done. The entire lower level is unfinished currently. Needs a driveway (crushed stone is common around here) and a garage would and a ton for minimal expense (unattached steel building, pole built.) A huge, nice deck off the back needs stairs added to get down to the ground. 

I'd put my rehab budget around $15,000 (doing the items that make sense myself - i.e. not the roof.) 

So if I have a HELOC or Business LOC at 5%, and do interest only on $50k, that puts my payment at $210/month, taxes at $275/month.

If it takes me 4 months to do (trying to be safe) my holding costs are $2,000. 

I would put ARV at $90,000 on the low end, and would probably start the listing at $109,000.

My question: what am I missing? Aside from potentially blowing re rehab budget, what are the risks I'm not seeing? 

If it blows by, that's fine - I'd rather have no deal than a bad deal because I rushed it and played a game I'm not too familiar with (flipping, that is - I actually like doing rehab.)  I'm just looking at taking the profit to buy another small multi this year (assuming I can find them.) 

Thanks!